Engine Control System & Fuel System - 4.6l - Introduction (2 of 2) Cadillac DTS I

Temperature Versus Resistance

Altitude Versus Barometric Pressure

Ignition System Specifications

Fastener Tightening Specifications

Scheme 1

Scheme 2

Scheme 3

Scheme 4

Scheme 5

Scheme 6

Scheme 7

Scheme 8

Scheme 9

Scheme 10

Scheme 11

Scheme 12

Scheme 13

DIAGNOSTIC CODE INDEX

DIAGNOSTIC CODE INDEX

Engine Control Module Replacement

Note. Turn the ignition OFF when installing or removing the control module connectors and disconnecting or reconnecting the power to the control module (battery cable, powertrain control module (PCM)/engine control module (ECM)/transaxle control module (TCM) pigtail, control module fuse, jumper cables, etc.) in order to prevent internal control module damage. Control module damage may result when the metal case contacts battery voltage. DO NOT contact the control module metal case with battery voltage when servicing a control module, using battery booster cables, or when charging the vehicle battery. In order to prevent any possible electrostatic discharge damage to the control module, do no touch the connector pins or the soldered components on the circuit board. Remove any debris from around the control module connector surfaces before servicing the control module. Inspect the control module connector gaskets when diagnosing or replacing the control module. Ensure that the gaskets are installed correctly. The gaskets prevent contaminant intrusion into the control module. The replacement control module must be programmed.

Removal Procedure

1. Using a scan tool, retrieve the percentage of remaining engine oil and automatic transaxle fluid life. Record the remaining engine oil and transaxle fluid life.
2. Ensure that the ignition is in the OFF position.
3. Disconnect the negative battery cable. Refer to «Battery Negative Cable Disconnection and Connection»(/cadillac/dts/i-2005-2011/remont/charging-system/#battery-charging-system-and-starting-system) .
4. Disconnect the engine harness electrical connector from the mass air flow/intake air temperature (MAF/IAT) sensor.
5. Disconnect the positive crankcase ventilation (PCV) fresh air tube quick connect fitting from the air duct. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
6. Disconnect the secondary air injection (AIR) pump inlet tube quick connect fitting from the air cleaner upper housing. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
7. Loosen the air cleaner outlet duct clamp at the throttle body.
8. Remove the air cleaner outlet duct from the throttle body.
9. Disengage the lower housing clips (1).
10. Disengage the upper housing front tabs from the lower housing.
11. Remove the air cleaner upper housing.
12. Disengage the engine harness electrical connector lever locks at the ECM.
13. Remove the engine harness electrical connectors from the ECM.
14. Remove the ECM from the air cleaner lower housing.

Installation Procedure

1. Install the ECM to the lower air cleaner housing.
2. Install the engine harness electrical connectors to the ECM.
3. Engage the engine harness electrical connector lever locks at the ECM.
4. Install the air cleaner upper housing.
5. Engage the upper housing front tabs to the lower housing.
6. Engage the lower housing clips (1).
7. Install the air cleaner outlet duct to the throttle body.
8. Tighten the air cleaner outlet duct clamp at the throttle body. Tighten: Tighten the clamp to 3 N.m (27 lb in).
9. Connect the AIR pump inlet tube quick connect fitting to the air cleaner upper housing. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
10. Connect the PCV fresh air tube quick connect fitting to the air duct. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
11. Connect the engine harness electrical connector to the MAF/IAT sensor.
12. Connect the negative battery cable. Refer to «Battery Negative Cable Disconnection and Connection»(/cadillac/dts/i-2005-2011/remont/charging-system/#battery-charging-system-and-starting-system) .
13. Program the ECM. Refer to «Control Module References»(/cadillac/dts/i-2005-2011/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) .

Crankshaft Position System Variation Learn

1. Install a scan tool.
2. Monitor the ECM for DTCs with a scan tool. If other DTCs are set, except DTC P0315, refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/cadillac/dts/i-2005-2011/remont/oem-general-information/#vehicle-diagnostic-information__diagnostic-trouble-code-dtc-list) for the applicable DTC that set.
3. With a scan tool, select the CKP system variation learn procedure within the Module Setup menu and perform the following: Observe the fuel cut-off for the applicable engine. Block the drive wheels. Set the parking brake. Place the vehicle's transmission in Park or Neutral. Turn the air conditioning (A/C) OFF. Cycle the ignition from OFF to ON. Apply and hold the brake pedal for the duration of the procedure. Start and idle the engine. Accelerate to wide open throttle (WOT). The engine should not accelerate beyond the calibrated fuel cut-off RPM value noted in step 3.1. Release the throttle immediately if the value is exceeded. IMPORTANT: While the learn procedure is in progress, release the throttle immediately when the engine starts to decelerate. The engine control is returned to the operator and the engine responds to throttle position after the learn procedure is complete. Release the throttle when fuel cut-off occurs.
4. The scan tool displays Learn Status: Learned this Ignition. If the scan tool indicates that DTC P0315 ran and passed, the CKP variation learn procedure is complete. If the scan tool indicates DTC P0315 failed or did not run, or if any other DTCs set, refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/cadillac/dts/i-2005-2011/remont/oem-general-information/#vehicle-diagnostic-information__diagnostic-trouble-code-dtc-list) for the applicable DTC that set.
5. Turn OFF the ignition for 30 seconds after the learn procedure is completed successfully.

Note. Use care when handling the coolant sensor. Damage to the coolant sensor will affect the operation of the fuel control system.

1. Remove the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .
2. Drain the cooling system. Refer to «Cooling System Draining and Filling (Vac-N-Fill)»(/cadillac/dts/i-2005-2011/remont/cooling-system-mechanical/#engine-cooling-system__cooling-system-draining-filling-vac-n-fill) or «Cooling System Draining and Filling (Static Fill)»(/cadillac/dts/i-2005-2011/remont/cooling-system-mechanical/#engine-cooling-system__cooling-system-draining-filling-static) .
3. Disconnect the engine harness electrical connector (6) from the engine coolant temperature (ECT) sensor.
4. Remove the ECT sensor.

Note. Use care when handling the coolant sensor. Damage to the coolant sensor will affect the operation of the fuel control system.

Note. Replacement components must be the correct part number for the application. Components requiring the use of the thread locking compound, lubricants, corrosion inhibitors, or sealants are identified in the service procedure. Some replacement components may come with these coatings already applied. Do not use these coatings on components unless specified. These coatings can affect the final torque, which may affect the operation of the component. Use the correct torque specification when installing components in order to avoid damage.

1. Apply sealant GM P/N 12346004 (Canadian P/N 10953480) or equivalent to the threads of the ECT sensor.
2. Install the ECT sensor. Tighten: Tighten the sensor to 20 N.m (15 lb ft).
3. Connect the engine harness electrical connector (6) to the ECT sensor.
4. Fill the cooling system. Refer to «Cooling System Draining and Filling (Vac-N-Fill)»(/cadillac/dts/i-2005-2011/remont/cooling-system-mechanical/#engine-cooling-system__cooling-system-draining-filling-vac-n-fill) or «Cooling System Draining and Filling (Static Fill)»(/cadillac/dts/i-2005-2011/remont/cooling-system-mechanical/#engine-cooling-system__cooling-system-draining-filling-static) .
5. Install the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .

Note. Handle the MAF sensor carefully. Do not drop the MAF sensor in order to prevent damage to the MAF sensor. Do not damage the screen located on the air inlet end of the MAF. Do not touch the sensing elements. Do not allow solvents and lubricants to come in contact with the sensing elements. Use a small amount of a soap based solution in order to aid in the installation.

1. Disconnect the engine harness electrical connector from the mass air flow/intake air temperature (MAF/IAT) sensor.
2. Loosen the air cleaner outlet duct clamp at the throttle body.
3. Loosen the air cleaner outlet duct clamp at the MAF/IAT sensor.
4. Remove the air cleaner outlet duct.
5. Remove the MAF/IAT sensor bolts.
6. Remove the MAF/IAT sensor.

Note. Handle the MAF sensor carefully. Do not drop the MAF sensor in order to prevent damage to the MAF sensor. Do not damage the screen located on the air inlet end of the MAF. Do not touch the sensing elements. Do not allow solvents and lubricants to come in contact with the sensing elements. Use a small amount of a soap based solution in order to aid in the installation.

1. Install the MAF/IAT sensor.
2. Install the MAF/IAT sensor bolts. Tighten: Tighten the bolts to 4 N.m (35 lb in).
3. Install the air cleaner outlet duct.
4. Tighten the air cleaner outlet duct clamp at the MAF/IAT sensor. Tighten: Tighten the clamp to 4 N.m (35 lb in).
5. Tighten the air cleaner outlet duct clamp at the throttle body. Tighten: Tighten the clamp to 4 N.m (35 lb in).
6. Connect the engine harness electrical connector to the MAF/IAT sensor.

1. Remove the fuel injector sight shield, if necessary. Refer to «Fuel Injector Sight Shield Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .
2. Disconnect the engine harness electrical connector (4) from the manifold absolute pressure (MAP) sensor.
3. Remove the MAP sensor bracket bolt.
4. Remove the MAP sensor bracket.
5. Remove the MAP sensor.

1. Install the MAP sensor.
2. Install the MAP sensor bracket.
3. Install the MAP sensor bracket bolt. Tighten: Tighten the bolt to 10 N.m (89 lb in).
4. Connect the engine harness electrical connector (4) to the MAP sensor.
5. Install the fuel injector sight shield, if necessary. Refer to «Fuel Injector Sight Shield Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .

Note. Handle the oxygen sensors carefully in order to prevent damage to the component. Keep the electrical connector and the exhaust inlet end free of contaminants. Do not use cleaning solvents on the sensor. Do not drop or mishandle the sensor.

Note. Refer to Heated Oxygen Sensor Resistance Learn Reset Notice .

1. Remove the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .
2. Remove the connector position assurance (CPA) retainer (3).
3. Disconnect the engine harness electrical connector (2) from the heated oxygen sensor (HO2S).
4. Remove the HO2S clip (5) from the secondary air injection (AIR) check valve hose bracket.
5. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/dts/i-2005-2011/remont/hoistjack/#general-information__lifting-jacking-the-vehicle) .
6. Support the rear of the frame with a tall screw type jack.
7. Remove the 4 rearward frame to body bolts (1) (left side shown, right side similar).
8. Lower the screw type jack approximately 4 cm (1.5 in) but not more than 76 mm (3 inches), allowing the rear of the frame to lower.
9. Remove the HO2S.

1. If reusing the old HO2S, coat the threads with anti-sieze compound, GM P/N 12377953 or equivalent.
2. Install the HO2S. Tighten: Tighten the sensor to 41 N.m (30 lb ft).
3. Raise the engine frame into position.
4. Install the 4 rearward frame to body bolts (1) (left side shown, right side similar). Tighten: Tighten the bolts to 191 N.m (141 lb ft).
5. Remove the screw type jack.
6. Install the HO2S clip (5) to the AIR check valve hose bracket.
7. Connect the engine harness electrical connector (2) to the HO2S.
8. Install the CPA retainer (3).
9. Install the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .

Note. Handle the oxygen sensors carefully in order to prevent damage to the component. Keep the electrical connector and the exhaust inlet end free of contaminants. Do not use cleaning solvents on the sensor. Do not drop or mishandle the sensor.

Note. Refer to Heated Oxygen Sensor Resistance Learn Reset Notice .

1. Remove the oxygen sensor wiring harness heat shield. Refer to «Oxygen Sensor Wiring Harness Heat Shield Replacement»(/cadillac/dts/i-2005-2011/remont/exhaust/#engine-exhaust-system) .
2. Disconnect the engine harness electrical connector from the heated oxygen sensor (HO2S).
3. Remove the HO2S.

1. If reusing the old HO2S, coat the threads with anti-sieze compound, GM P/N 12377953 or equivalent.
2. Install the HO2S. Tighten: Tighten the sensor to 41 N.m (30 lb ft).
3. Connect the engine harness electrical connector to the HO2S.
4. Install the oxygen sensor wiring harness heat shield. Refer to «Oxygen Sensor Wiring Harness Heat Shield Replacement»(/cadillac/dts/i-2005-2011/remont/exhaust/#engine-exhaust-system) .

Note. Handle the oxygen sensors carefully in order to prevent damage to the component. Keep the electrical connector and the exhaust inlet end free of contaminants. Do not use cleaning solvents on the sensor. Do not drop or mishandle the sensor.

Note. Refer to Heated Oxygen Sensor Resistance Learn Reset Notice .

1. Remove the air deflector. Refer to «Front Air Deflector Replacement»(/cadillac/dts/i-2005-2011/remont/exterior-body-panels/#bumper-system-fascia) .
2. Remove the connector position assurance (CPA) retainer.
3. Disconnect the engine harness electrical connector (3) from the heated oxygen sensor (HO2S).
4. Remove the HO2S clip (2) from the engine bracket.
5. Remove the HO2S.

1. If reusing the old HO2S, coat the threads with anti-sieze compound, GM P/N 12377953 or equivalent.
2. Install the HO2S. Tighten: Tighten the sensor to 41 N.m (30 lb ft).
3. Connect the engine harness electrical connector (3) to the HO2S.
4. Install the CPA retainer.
5. Install the HO2S clip (2) to the engine bracket.
6. Install the air deflector. Refer to «Front Air Deflector Replacement»(/cadillac/dts/i-2005-2011/remont/exterior-body-panels/#bumper-system-fascia) .

1. Remove the left instrument panel (I/P) sound insulator. Refer to «Instrument Panel Insulator Panel Replacement - Left Side»(/cadillac/dts/i-2005-2011/remont/exteriorinterior-trim/#instrument-panel-trim-and-console-trim) .
2. Disconnect the body harness electrical connector (1) from the accelerator pedal position (APP) sensor.
3. Remove the accelerated pedal nuts.
4. Remove the accelerator pedal.

1. Install the accelerator pedal.
2. Install the accelerated pedal nuts. Tighten: Tighten the nuts to 10 N.m (89 lb in).
3. Connect the body harness electrical connector (1) to the APP sensor.
4. Install the left I/P sound insulator. Refer to «Instrument Panel Insulator Panel Replacement - Left Side»(/cadillac/dts/i-2005-2011/remont/exteriorinterior-trim/#instrument-panel-trim-and-console-trim) .

1. Remove the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .
2. Remove the air cleaner outlet duct. Refer to «Air Cleaner Outlet Duct Replacement»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
3. Disconnect the positive crankcase ventilation (PCV) fresh air tube quick connect fittings at the camshaft cover and the air cleaner outlet duct. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
4. Remove the PCV fresh air tube.
5. Disconnect the engine harness electrical connector (5) from the throttle actuator.
6. Remove the transaxle vent hose clip (1) from the shift cable bracket.
7. Remove the transaxle shift cable clip from the shift cable bracket.
8. Remove the throttle body bolts.
9. Remove the shift cable bracket.
10. Remove the throttle body.
11. Remove and discard the throttle body seal.

1. Install a NEW throttle body seal.
2. Position the throttle body.
3. Position the shift cable bracket.
4. Install the throttle body bolts. Tighten: Tighten the bolts to 10 N.m (89 lb in).
5. Install the transaxle shift cable clip to the shift cable bracket.
6. Install the transaxle vent hose clip (1) to the shift cable bracket.
7. Connect the engine harness electrical connector (5) to the throttle actuator.
8. Install the PCV fresh air tube.
9. Connect the PCV fresh air tube quick connect fittings at the camshaft cover and the air cleaner outlet duct. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
10. Install the air cleaner outlet duct. Refer to «Air Cleaner Outlet Duct Replacement»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
11. Install the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .

Description

The engine control module (ECM) learns the idle position of the throttle plate to ensure the correct idle. The learned airflow values are stored within the ECM. These values are learned to adjust for production variation and will continuously learn during the life of the vehicle to compensate for reduced airflow due to coking. Anytime the throttle body airflow rate changes, for example due to cleaning or replacing, the values must be relearned.

A vehicle that had a heavily coked throttle body that has been cleaned or replaced may take several drive cycles to learn out the coking. To accelerate the process, the scan tool has the ability to reset all learned values back to zero. A new ECM will also have values set to zero.

The idle may be unstable or a DTC may set if the learned values do not match the actual airflow.

Conditions for Running the Throttle Learn Procedure

With Scan Tool - Reset

1. DTCs P0101, P0102, P0103, P0107, P0108, P0111, P0112, P0113, P0506, and P0507 are not set.
2. Ignition ON, engine OFF.
3. The vehicle speed sensor (VSS) is 0 km/h (0 mph).

Without Scan Tool - Learn

1. DTCs P0101, P0102, P0103, P0107, P0108, P0111, P0112, P0113, P0506, and P0507 are not set.
2. The engine speed is between 450-4,000 RPM.
3. The manifold absolute pressure (MAP) is greater than 5 kPa.
4. The mass air flow (MAF) is greater than 2 g/s.
5. The ignition 1 voltage is greater than 10 volts.

Throttle Learn

With Scan Tool - Reset

1. Ignition ON, engine OFF. With a scan tool, perform the Idle Learn Reset in Module Setup.
2. Start the engine, monitor the TB Idle Airflow Compensation parameter. The TB Idle Airflow Compensation parameter value should equal 0 percent and the engine should be idling at a normal idle speed. If the engine is not idling normally, proceed with the Learn portion of the diagnostic.
3. Clear the DTCs and return to the diagnostic that referred you here.

Without Scan Tool-Learn

1. DTCs P0101, P0102, P0103, P0107, P0108, P0111, P0112, P0113, P0506, and P0507 are not set.
2. The engine speed is between 450-4,000 RPM.
3. The manifold absolute pressure (MAP) is greater than 5 kPa.
4. The mass air flow (MAF) is greater than 2 g/s.
5. The ignition 1 voltage is greater than 10 volts.
6. Start and idle the engine in PARK for 3 minutes.
7. With a scan tool, monitor desired and actual RPM.
8. The ECM will start to learn the new idle cells and Desired RPM should start to decrease.
9. Ignition OFF for 60 seconds.
10. Start and idle the engine in PARK for 3 minutes.
11. After the 3 minute run time the engine should be idling normal. IMPORTANT: During the drive cycle the check engine light may come on with idle speed DTCs. If idle speed codes are set, clear codes so the ECM can continue to learn. If the engine idle speed has not been learned the vehicle will need to be driven at speeds above 70 km/h (44 mph) with several decelerations and extended idles.
12. After the drive cycle, the engine should be idling normally. If the engine idle speed has not been learned, turn OFF the ignition for 60 seconds and repeat step 6.
13. Once the engine speed has returned to normal, clear DTCs.

Throttle Body Inspection & Cleaning

1. Remove the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .
2. Remove the air cleaner outlet duct.
3. Inspect the throttle body bore and the throttle body plate for deposits. You will need to open the throttle plate in order to inspect all surfaces.
4. Clean the throttle body bore and the throttle plate using a clean shop towel with GM top engine cleaner, P/N 1052626 or AC Delco Carburetor Tune-up Conditioner P/N X66P or an equivalent product.
5. Install the air cleaner outlet duct.
6. Install the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .

Special Tools

CH-48027 Digital Pressure gauge. See Special Tools .

Pressure Relief Procedure

1. If the fuel system requires repair, prevent fuel spillage by removing the fuel pump fuse. Refer to «Electrical Center Identification Views»(/cadillac/dts/i-2005-2011/remont/electrical-component-locations/#wiring-systems-and-power-management-component-locator-component-connector-end-views) .
2. Remove the engine cover, if required.
3. Loosen the fuel fill cap in order to relieve the fuel tank vapor pressure.
4. Remove the fuel rail service port cap.
5. Wrap a shop towel around the fuel rail service port.
6. Connect the CH-48027-3 (4) to the fuel rail service port.
7. Connect the CH-48027-2 (2) to the CH-48027-3 (4).
8. Place the hose on the CH-48027-2 (2) into an approved gasoline container.
9. Open the valve on the CH-48027-2 (2) in order to bleed any fuel from the fuel rail.
10. Close the valve on the CH-48027-2 (2).
11. Remove the hose on the CH-48027-2 (2) from the approved gasoline container.
12. Disconnect the CH-48027-2 (2) from the CH-48027-3 (4).
13. Disconnect the CH-48027-3 (4) from the fuel rail service port.
14. Remove the shop towel from around the fuel rail service port, and place in an approved gasoline container.
15. Install the fuel rail service port cap.
16. Install the engine cover, if required.
17. Tighten the fuel fill cap.

Fuel Pressure Relief (Without CH 48027)

1. If the fuel system requires repair, prevent fuel spillage by removing the fuel pump fuse. Refer to «Electrical Center Identification Views»(/cadillac/dts/i-2005-2011/remont/electrical-component-locations/#wiring-systems-and-power-management-component-locator-component-connector-end-views) .
2. Loosen the fuel fill cap in order to relieve the fuel tank vapor pressure.
3. Remove the engine cover, if required.
4. Remove the fuel rail service port cap.
5. Wrap a shop towel around the fuel rail service port and using a small flat-bladed tool, depress (open) the fuel rail test port valve.
6. Remove the shop towel from around the fuel rail service port, and place in an approved gasoline container.
7. Install the fuel rail service port cap.
8. Install the engine cover, if required.
9. Tighten the fuel fill cap.

Tools Required

CH-48027 Digital Pressure gauge. See Special Tools .

1. Relieve the fuel system pressure. Refer to «Fuel Pressure Relief (With CH 48027)»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) or «Fuel Pressure Relief (Without CH 48027)»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2__fuel-pressure-relief-without-ch-48027) .
2. Connect the CH-48027-1 (1) to the CH-48027-2 (2).
3. Remove the shop towel from around the fuel rail service port, and place in an approved gasoline container.
4. Perform any tests and/or diagnostics as needed. For the proper usage of the CH-48027 , refer to the manufacture's directions. See «Special Tools»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .

1. Relieve the fuel system pressure, if required. Perform the following steps: CAUTION: Wrap a shop towel around the fuel pressure connection in order to reduce the risk of fire and personal injury. The towel will absorb any fuel leakage that occurs during the connection of the fuel pressure gauge. Place the towel in an approved container when the connection of the fuel pressure gauge is complete. Wrap a shop towel around the fuel rail service port. Place the hose on the CH-48027-2 (2) into an approved gasoline container. Open the valve on the CH-48027-2 (2) in order to bleed any fuel from the fuel rail. Close the valve on the CH-48027-2 (2). Remove the hose on the CH-48027-2 (2) from the approved gasoline container. Remove the shop towel from around the fuel rail service port, and place in an approved gasoline container.
2. Disconnect the CH-48027-1 (1) from the CH-48027-2 (2).
3. Disconnect the CH-48027-2 (2) from the CH-48027-3 (4).
4. Disconnect the CH-48027-3 (4) from the fuel rail service port.
5. Install the fuel rail service port cap.
6. Install the engine cover, if required.
7. Tighten the fuel fill cap.

J 37088-A Fuel Line Disconnect Tool Set. See Special Tools .

1. Relieve the fuel system pressure. Refer to «Fuel Pressure Relief (With CH 48027)»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) or «Fuel Pressure Relief (Without CH 48027)»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2__fuel-pressure-relief-without-ch-48027) .
2. Remove the retainer from the quick-connect fitting.
3. Blow dirt out of the fitting using compressed air.
4. Choose the correct tool from the fuel line disconnect tool set for the size of the fitting. Insert the tool into the female connector, then push inward to release the locking tabs.
5. Pull the connection apart.
6. Using a clean shop towel, wipe off the male pipe end.
7. Inspect both ends of the fitting for dirt and burrs. Clean or replace the components as required.

1. Apply a few drops of clean engine oil to the male pipe end.
2. Push both sides of the fitting together to cause the retaining tabs to snap into place.
3. Once installed, pull on both sides of the fitting to make sure the connection is secure.
4. Install the retainer to the quick-connect fitting.

1. If servicing the secondary air injection (AIR) hose/pipe quick connect fitting perform the following step. If servicing the fuel and/or evaporative emission (EVAP) quick connect fittings proceed to step 3.
2. Squeeze where indicated by the arrows on both sides of the plastic ring surrounding the quick connect fitting.
3. Relieve the fuel system pressure. Refer to «Fuel Pressure Relief (With CH 48027)»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) or «Fuel Pressure Relief (Without CH 48027)»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2__fuel-pressure-relief-without-ch-48027) .
4. Using compressed air, blow any dirt out of the quick connect fitting.
5. This step applies to the Bartholomew style connectors ONLY. Squeeze the plastic quick connect fitting release tabs.
6. This step applies to the Q release type connectors ONLY. Release the fitting by pushing the tab toward the other side of the slot in the fitting.
7. This step applies to the Squeeze to release style connectors ONLY. Squeeze where indicated by arrows on both sides of the plastic ring surrounding the quick connect fitting.
8. This step also applies to the Squeeze to release style connectors ONLY. Squeeze where indicated by the arrows on both sides of the plastic ring surrounding the quick connect fitting.
9. This step applies to the Sliding retainer style connectors ONLY. Release the fitting by pressing on one side of the release tab causing it to push in slightly. If the tab does not move, try pressing the tab in from the opposite side. the tab will only move in one direction.
10. This step applies to the Push down TI style connectors ONLY. Release the fitting by pressing on the tabs indicated by the arrow.
11. Pull the connection apart.
12. Wipe off the male pipe end using a clean shop towel.
13. Inspect both ends of the fitting for dirt and burrs.
14. Clean or replace the components as required.

1. If servicing the fuel and/or EVAP quick connect fittings perform the following steps. If servicing the AIR pipe/hose quick connect fitting proceed to step 5.
2. Apply a few drops of clean engine oil to the male connection end.
3. Push both sides of the quick connect fitting together in order to cause the retaining feature to snap into place.
4. Once installed, pull on both sides of the quick connect fitting in order to make sure the connection is secure.
5. Push the quick connect fitting on until an audible click is hear, once installed, gently pull on the quick connect fitting in order to make sure the connection is secure.

1. J 36850 Transjel Lubricant. See «Special Tools»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
2. J 42960-2 Fuel Flapper Door Holder. See «Special Tools»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
3. J 45004 Fuel Drain Hose. See «Special Tools»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .

Note. Drain the fuel tank with a hose which has a 13 mm (0.5 in) or smaller diameter in order to prevent the drain hose from getting stuck inside the fuel tank filler neck pipe check valve. Damage to the check valve may result.

Draining Procedure

1. Remove the fuel fill cap (1)
2. Install the J 42960-2 into the fuel fill pipe in order to hold the door open. See «Special Tools»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
3. Insert the J 45004 into the fuel tank until the hose reaches the bottom of the fuel tank. See «Special Tools»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
4. Use an air operated pump device in order to drain the fuel into an approved gasoline container.
5. Simultaneously twist and pull in order to remove the J 45004 from the fuel tank. See «Special Tools»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .

J 45722 Fuel Sender Lock Ring Wrench. See Special Tools .

1. Relieve the fuel system pressure. Refer to «Fuel Pressure Relief (With CH 48027)»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) or «Fuel Pressure Relief (Without CH 48027)»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2__fuel-pressure-relief-without-ch-48027) .
2. Drain the fuel tank. Refer to «Fuel Tank Draining»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
3. Remove the left rear wheel house liner. Refer to «Rear Wheelhouse Panel Liner Replacement»(/cadillac/dts/i-2005-2011/remont/frames-subframes-crossmembers/#frame-and-underbody) .
4. Using compressed air, blow any dirt and/or debris from around the fuel fill pipe and evaporative emission (EVAP) line connections.
5. Loosen the fuel fill hose clamp (1) at the fill pipe.
6. Disconnect the fuel fill hose (2) from the fuel fill pipe.
7. Disconnect the fuel tank EVAP recirculation line quick connect fitting (1) from the fill pipe line. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
8. Disconnect the automatic level control sensor link from the left rear suspension control arm, if equipped.
9. Disconnect the left and right electronic position sensor links from the ball studs. (left side shown, right side similar) (regular production option (RPO) F55 shown, F38 similar).
10. Disconnect the fill pipe vent line (2) and the fuel tank vapor line (3) quick connect fittings from the EVAP canister. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
11. Disconnect the fuel feed line quick connect fitting (1) from the chassis line. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
12. Remove the fuel and EVAP line retainer (1) from the side rail.
13. Disconnect the body harness electrical connector from the fuel tank harness electrical connector (1).
14. Remove the fuel tank harness clips (2, 3) from the rear compartment side rail.
15. Remove the exhaust system. Refer to «Exhaust System Replacement»(/cadillac/dts/i-2005-2011/remont/exhaust/#engine-exhaust-system) .
16. Loosen the left and right rear brake hose bracket nut and slide the stud out of the keyhole slot in the side rail. (left side shown, right side similar).
17. Remove the rear shock bolts.
18. Support the front of the vehicle with a jack stand at the engine cradle.
19. Support the rear suspension crossmember with a suitable adjustable jack.
20. Remove the rear suspension crossmember bolts.
21. Using the adjustable jack (1), slowly lower the rear suspension crossmember allowing the crossmember to pivot at the front bolts, until the rear springs can be removed.
22. Remove the rear coil springs.
23. Remove the fuel tank strap bolts.
24. Remove the fuel tank straps.
25. Remove the fuel tank.
26. Place the fuel tank on a suitable work surface.
27. Disconnect the fuel tank electrical harness connectors from the module and pressure sensor.
28. Remove the electrical harness.
29. Disconnect the fuel feed line quick connect fitting from the module. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
30. Remove the fuel feed line from the retaining feature in the fuel tank.
31. Remove the fuel feed line.
32. Install the J 45722 to the lock ring. See «Special Tools»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
33. Use the J 45722 and a long breaker bar in order to unlock the fuel module lock ring. See «Special Tools»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) . Rotate the lock ring in a counterclockwise direction.
34. Remove the J 45722 and the fuel module lock ring. See «Special Tools»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
35. Slowly raise the module until the fuel level sensor float arm is just visible.
36. Tilt the module toward the rear of the fuel tank to allow the level sensor float arm to clear the tank opening. Remove the module from the tank.
37. Carefully discard the fuel in the module bucket into an approved container.
38. Remove and discard the fuel pump module O-ring seal.
39. Place the lock ring on a flat surface. Measure the clearance between the lock ring and the flat surface using a feeler gauge at 7 different points.
40. If the warpage is less than 0.41 mm (0.016 in), the lock ring does not require replacement.
41. If the warpage is greater than 0.41 mm (0.016 in), the lock ring must be replaced.

1. Place a NEW fuel pump module O-ring seal onto the fuel tank.
2. Tilt the module toward the rear of the fuel tank to allow the fuel level sensor float arm to clear the tank opening. Install the module into the fuel tank.
3. Lower the module assembly into the tank.
4. Install the module lock ring, and move it into position on the top of the module.
5. Install the J 45722 to the lock ring. See «Special Tools»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
6. Using the J 45722 and a breaker bar, rotate the fuel pump module lock ring clockwise until the ring is locked into place on the fuel tank. See «Special Tools»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
7. Remove the J 45722 . See «Special Tools»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
8. Install the fuel feed line.
9. Connect the fuel feed line quick connect fitting to the module. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
10. Install the fuel feed line to the retaining feature in the fuel tank.
11. Install the electrical harness.
12. Connect the fuel tank electrical harness connectors to the module and pressure sensor.
13. Place the fuel tank onto the rear suspension crossmember.
14. Install the fuel tank straps.
15. Install the fuel tank strap bolts. Tighten: Tighten the bolts to 46 N.m (34 lb ft).
16. Install the rear coil springs while slowly raising the rear suspension crossmember using the adjustable jack (1).
17. Install the rear suspension crossmember bolts. Tighten: Tighten the bolts to 191 N.m (141 lb ft).
18. Remove the adjustable jack from the rear suspension crossmember.
19. Remove the jack stand from the front of the vehicle.
20. Install the rear shock bolts. Tighten: Tighten the bolts to 25 N.m (18 lb ft).
21. Connect the body harness electrical connector to the fuel tank harness electrical connector (1).
22. Install the fuel tank harness clips (2, 3) to the rear compartment side rail.
23. Install the fuel and EVAP line retainer (1) to the side rail.
24. Connect the fuel feed line quick connect fitting (1) to the chassis line. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
25. Connect the fill pipe vent line (2) and the fuel tank vapor line (3) quick connect fittings to the EVAP canister. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
26. Install the left and right rear brake hose bracket studs into the keyhole slots. Tighten the nuts. (left side shown, right side similar). Tighten: Tighten the nut to 10 N.m (89 lb in).
27. Install the exhaust system. Refer to «Exhaust System Replacement»(/cadillac/dts/i-2005-2011/remont/exhaust/#engine-exhaust-system) .
28. Connect the left and right electronic position sensor links to the ball studs. (left side shown, right side similar) (RPO F55 shown, F38 similar).
29. Connect the automatic level control sensor link to the left rear suspension control arm, if equipped.
30. Connect the fuel tank EVAP recirculation line quick connect fitting (1) to the fill pipe line. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
31. Connect the fuel fill hose (2) to the fuel fill pipe.
32. Tighten the fuel fill hose clamp (1) at the fill pipe. Tighten: Tighten the clamp to 4 N.m (35 lb in).
33. Install the left rear wheel house liner. Refer to «Rear Wheelhouse Panel Liner Replacement»(/cadillac/dts/i-2005-2011/remont/frames-subframes-crossmembers/#frame-and-underbody) .
34. Fill the fuel tank.
35. Connect the negative battery cable. Refer to «Battery Negative Cable Disconnection and Connection»(/cadillac/dts/i-2005-2011/remont/charging-system/#battery-charging-system-and-starting-system) .
36. Perform the following procedure in order to inspect for leaks: Turn ON the ignition, with the engine OFF for 2 seconds. Turn OFF the ignition for 10 seconds. Turn ON the ignition, with the engine OFF. Inspect for fuel leaks.
37. Install the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .

1. Remove the fuel tank. Refer to «Fuel Tank Replacement»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
2. Disconnect the fuel level sensor wiring harness electrical connectors from the pressure sensor and module.
3. Remove the fuel level sensor wiring harness.

1. Install the fuel level sensor wiring harness.
2. Connect the fuel level sensor wiring harness electrical connectors to the pressure sensor and module.
3. Install the fuel tank. Refer to «Fuel Tank Replacement»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .

1. Remove the rear compartment liner. Refer to «Rear Compartment Liner Replacement»(/cadillac/dts/i-2005-2011/remont/exterior-body-panels/#bolted-exterior-body-panels-and-closures) .
2. Remove the fuel sender access hole cover bolts.
3. Remove the fuel sender access hole cover.
4. Disconnect the fuel level sensor wiring harness electrical connector (1) fuel tank pressure sensor.
5. Remove the fuel tank pressure sensor.

1. Install the fuel tank pressure sensor.
2. Connect the fuel level sensor wiring harness electrical connector (1) to the fuel tank pressure sensor.
3. place the fuel sender access hole cover into position.
4. Install the fuel sender access hole cover bolts. Tighten: Tighten the bolts to 2 N.m (18 lb in).
5. Install the rear compartment liner. Refer to «Rear Compartment Liner Replacement»(/cadillac/dts/i-2005-2011/remont/exterior-body-panels/#bolted-exterior-body-panels-and-closures) .

1. Remove the fuel pump module. Refer to «Fuel Sender Assembly Replacement»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
2. Release the fuel level sensor electrical connector clip.
3. Disconnect the fuel level sensor electrical connector (1) from under the fuel module cover.
4. Release the locking tab (2) and slide the fuel level sensor (3) down off of the bucket.

1. Slide the fuel level sensor (3) up onto the bucket, gently lift up on the locking tab (2) and continue sliding the sensor up until it engages the tab.
2. Connect the fuel level sensor electrical connector (1) under the module cover. Push up the connector until the clip engages.
3. Install the fuel pump module. Refer to «Fuel Sender Assembly Replacement»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .

1. Drain the fuel tank to a level below the fuel fill hose, if necessary. Refer to «Fuel Tank Draining»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
2. Remove the left rear wheel house liner. Refer to «Rear Wheelhouse Panel Liner Replacement»(/cadillac/dts/i-2005-2011/remont/frames-subframes-crossmembers/#frame-and-underbody) .
3. Using compressed air, blow any dirt and/or debris from around the fuel fill pipe and evaporative emission (EVAP) line connections.
4. Loosen the fuel fill hose clamp (1) at the fill pipe.
5. Disconnect the fuel fill hose (2) from the fuel fill pipe.
6. Disconnect the fuel tank EVAP recirculation line quick connect fitting (1) from the fill pipe line. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
7. Remove the fuel fill pipe ground strap bolt.
8. Disconnect the fill pipe vent line (2) quick connect fitting from the EVAP canister. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
9. Lower the vehicle.
10. Remove the fuel tank fill pocket opening grommet.
11. Remove the fuel tank fill pipe out through the opening in the pocket.

1. Install the fuel tank fill pipe in through the opening in the pocket.
2. Install the fuel tank fill pocket opening grommet. Ensure all 4 retaining tabs are seated.
3. Raise the vehicle.
4. Connect the fill pipe vent line (2) quick connect fitting to the EVAP canister. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
5. Position the ground strap to the bracket.
6. Install the fuel fill pipe ground strap bolt. Tighten: Tighten the bolt to 9 N.m (80 lb in).
7. Connect the fuel tank EVAP recirculation line quick connect fitting (1) to the fill pipe line. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
8. Connect the fuel fill hose (2) to the fuel fill pipe.
9. Tighten the fuel fill hose clamp (1) at the fill pipe. Tighten: Tighten the clamp to 4 N.m (35 lb in).
10. Install the left rear wheel house liner. Refer to «Rear Wheelhouse Panel Liner Replacement»(/cadillac/dts/i-2005-2011/remont/frames-subframes-crossmembers/#frame-and-underbody) .
11. Inspect the fuel tank fill pocket opening grommet. Ensure the grommet is seated flush to the body.
12. Connect the negative battery cable. Refer to «Battery Negative Cable Disconnection and Connection»(/cadillac/dts/i-2005-2011/remont/charging-system/#battery-charging-system-and-starting-system) .
13. Perform the following procedure in order to inspect for leaks: Turn ON the ignition, with the engine OFF for 2 seconds. Turn OFF the ignition for 10 seconds. Turn ON the ignition, with the engine OFF. Inspect for fuel leaks.
14. Install the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .

J 45722 Fuel Sender Lock Ring Wrench. See Special Tools .

1. Relieve the fuel system pressure. Refer to «Fuel Pressure Relief (With CH 48027)»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) or «Fuel Pressure Relief (Without CH 48027)»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2__fuel-pressure-relief-without-ch-48027) .
2. Remove the rear compartment liner. Refer to «Rear Compartment Liner Replacement»(/cadillac/dts/i-2005-2011/remont/exterior-body-panels/#bolted-exterior-body-panels-and-closures) .
3. Remove the fuel sender access hole cover bolts.
4. Remove the fuel sender access hole cover.
5. Disconnect the fuel feed rear pipe quick connect fitting (3) from the module. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
6. Disconnect the fuel level sensor wiring harness electrical connectors (1, 2) from the pressure sensor and module.
7. Reposition the fuel feed pipe and harness connectors out of the way.
8. Install the J 45722 to the lock ring. See «Special Tools»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
9. Use the J 45722 and a long breaker-bar in order to unlock the fuel module lock ring. See «Special Tools»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) . Rotate the lock ring in a counterclockwise direction.
10. Remove the J 45722 and the fuel module lock ring. See «Special Tools»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
11. Slowly raise the module until the fuel level sensor float arm is just visible.
12. Tilt the module toward the rear of the fuel tank to allow the level sensor float arm to clear the tank opening. Remove the module from the tank.
13. Carefully discard the fuel in the module reservoir bucket into an approved fuel container.
14. Remove and discard the fuel pump module O-ring seal.
15. Place the lock ring on a flat surface. Measure the clearance between to lock ring and the flat surface using a feeler gauge at 7 different points.
16. If the warpage is less than 0.41 mm (0.016 in), the lock ring does not require replacement.
17. If the warpage is greater than 0.41 mm (0.016 in), the lock ring must be replaced.

1. Place a NEW fuel pump module O-ring seal onto the fuel tank.
2. Tilt the module toward the rear of the fuel tank to allow the fuel level sensor float arm to clear the tank opening. Install the module into the fuel tank.
3. Lower the module assembly into the tank.
4. Install the module lock ring, and move it into position on the top of the module.
5. Install the J 45722 to the lock ring. See «Special Tools»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
6. Using the J 45722 and a breaker bar, rotate the fuel pump module lock ring clockwise until the ring is locked into place on the fuel tank. See «Special Tools»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
7. Remove the J 45722 . See «Special Tools»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
8. Position the fuel feed pipe and harness connectors.
9. Connect the fuel level sensor wiring harness electrical connectors (1, 2) to the pressure sensor and module.
10. Connect the fuel feed rear pipe quick connect fitting (3) to the module. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
11. Connect the negative battery cable. Refer to «Battery Negative Cable Disconnection and Connection»(/cadillac/dts/i-2005-2011/remont/charging-system/#battery-charging-system-and-starting-system) .
12. Perform the following procedure in order to inspect for leaks: Turn ON the ignition, with the engine OFF for 2 seconds. Turn OFF the ignition for 10 seconds. Turn ON the ignition, with the engine OFF. Inspect for fuel leaks.
13. Install the fuel sender access hole cover.
14. Install the fuel sender access hole cover bolts. Tighten: Tighten the bolts to 2 N.m (18 lb in).
15. Install the rear compartment liner. Refer to «Rear Compartment Liner Replacement»(/cadillac/dts/i-2005-2011/remont/exterior-body-panels/#bolted-exterior-body-panels-and-closures) .
16. Install the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .

1. Remove the fuel tank. Refer to «Fuel Tank Replacement»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
2. Disconnect the fuel feed rear pipe quick connect fitting at the module. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
3. Remove the fuel feed rear pipe from the retaining feature on the fuel tank.
4. Remove the fuel feed rear pipe.

1. Install the fuel feed rear pipe.
2. Connect the fuel feed rear pipe quick connect fitting at the module. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
3. Install the fuel feed rear pipe to the retaining feature on the fuel tank.
4. Install the fuel tank. Refer to «Fuel Tank Replacement»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .

1. Relieve the fuel system pressure. Refer to «Fuel Pressure Relief (With CH 48027)»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) or «Fuel Pressure Relief (Without CH 48027)»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2__fuel-pressure-relief-without-ch-48027) .
2. Clean the fuel and evaporative emission (EVAP) pipe connections and areas surrounding the connections prior to disconnecting the connections in order to avoid possible contamination of the fuel and/or EVAP system.
3. Disconnect the fuel feed pipe (1) quick connect fitting at the fuel rail. Refer to «Metal Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
4. Disconnect the EVAP line (2) quick connect fitting at the EVAP canister purge valve. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
5. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/dts/i-2005-2011/remont/hoistjack/#general-information__lifting-jacking-the-vehicle) .
6. Loosen the fuel/EVAP pipe retainer bolt (1).
7. Disconnect the fuel feed rear pipe quick connect fitting (1) from the chassis fuel line. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
8. Disconnect the chassis EVAP line quick connect fitting (1) from the EVAP canister. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
9. Drill out the rivets (5) securing the retainer (2) to the underbody.
10. Disconnect the retainers (3, 4 and 1) from the underbody.
11. Remove the fuel/EVAP lines from the vehicle and place on a suitable work surface.
12. Remove the fuel line from the retainers.

1. Install the fuel line to the retainers.
2. Position the fuel/EVAP lines to the vehicle underbody.
3. Connect the retainers (3, 4 and 1) to the underbody.
4. Install NEW rivets (5) securing the retainer (2) to the underbody
5. Connect the chassis EVAP line quick connect fitting (1) to the EVAP canister. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
6. Connect the fuel feed rear pipe quick connect fitting (1) to the chassis fuel line. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
7. Position the retainer to the front of dash.
8. Tighten the fuel/EVAP pipe retainer bolt (1). Tighten: Tighten the bolt to 6 N.m (53 lb in).
9. Lower the vehicle.
10. Connect the EVAP line (2) quick connect fitting at the EVAP canister purge valve. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
11. Connect the fuel feed pipe (1) quick connect fitting at the fuel rail. Refer to «Metal Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
12. Connect the negative battery cable. Refer to «Battery Negative Cable Disconnection and Connection»(/cadillac/dts/i-2005-2011/remont/charging-system/#battery-charging-system-and-starting-system) .
13. Perform the following procedure in order to inspect for leaks: Turn ON the ignition, with the engine OFF for 2 seconds. Turn OFF the ignition for 10 seconds. Turn ON the ignition, with the engine OFF. Inspect for fuel leaks.
14. Install the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .

1. Remove the fuel tank. Refer to «Fuel Tank Replacement»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
2. Loosen the fuel fill hose clamp (1) at the fuel tank.
3. Remove the fuel fill hose from the fuel tank.

1. Install the fuel fill hose to the fuel tank. Ensure that the notch (3) in the fill hose is aligned with the notch on the fuel tank.
2. Tighten the fuel fill hose clamp (1) at the fuel tank. Tighten: Tighten the fuel filler hose clamp to 4 N.m (35 lb in).
3. Install the fuel tank. Refer to «Fuel Tank Replacement»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .

Fuel System Cleaning

1. Remove the fuel sender assembly. Refer to «Fuel Sender Assembly Replacement»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
2. Inspect the fuel sender strainer. Replace the fuel sender assembly if the fuel strainer is contaminated.
3. Flush the fuel tank with hot water.
4. Pour the water out of the fuel sender assembly opening in the fuel tank. Rock the fuel tank in order to be sure that the removal of the water from the fuel tank is complete.
5. Install the fuel sender assembly. Refer to «Fuel Sender Assembly Replacement»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .

Note. Remove the fuel rail assembly carefully in order to prevent damage to the injector electrical connector terminals and the injector spray tips. Support the fuel rail after the fuel rail is removed in order to avoid damaging the fuel rail components. Cap the fittings and plug the holes when servicing the fuel system in order to prevent dirt and other contaminants from entering open pipes and passages.

1. Relieve the fuel system pressure. Refer to the «Fuel Pressure Relief (With CH 48027)»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) or «Fuel Pressure Relief (Without CH 48027)»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2__fuel-pressure-relief-without-ch-48027) .
2. Clean the fuel rail assembly with a spray type engine cleaner, GM X-30A or equivalent, if necessary. Follow the package instructions. Do not soak the fuel rail in liquid cleaning solvent.
3. Disconnect the fuel feed pipe quick connect fitting (1) from the fuel rail. Refer to «Metal Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
4. Disconnect the positive crankcase ventilation (PCV) air tube quick connect fitting from the camshaft cover. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
5. Reposition the surge tank inlet pipe hose clamp at the surge tank.
6. Remove the surge tank inlet pipe hose from the surge tank.
7. Reposition the surge tank inlet pipe hose clamp at the engine fitting.
8. Remove the surge tank inlet pipe hose from the engine fitting.
9. Remove the surge tank inlet pipe nuts.
10. Remove the surge tank inlet pipe from the fuel rail studs.
11. Disconnect the engine harness electrical connector (1) from the starter solenoid cable electrical connector.
12. Disconnect the engine harness electrical connectors (3) from the front fuel injectors.
13. Disconnect the engine harness electrical connectors (1) from the rear fuel injectors.
14. Remove the engine harness clip (2) from the fuel rail stud.
15. Lay the harness aside.
16. Remove the fuel rail bracket retainer nut (2).
17. Remove the fuel rail studs (1).
18. Remove the fuel rail.
19. Remove and discard the O-ring seals (4) from the spray tip end of each fuel injector.
20. If replacing the fuel rail, remove the fuel injectors. Refer to «Fuel Injector Replacement»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .

Note. Use care when servicing the fuel system components, especially the fuel injector electrical connectors, the fuel injector tips, and the injector O-rings. Plug the inlet and the outlet ports of the fuel rail in order to prevent contamination. Do not use compressed air to clean the fuel rail assembly as this may damage the fuel rail components. Do not immerse the fuel rail assembly in a solvent bath in order to prevent damage to the fuel rail assembly.

1. If the fuel rail was replaced, install the fuel injectors. Refer to «Fuel Injector Replacement»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
2. Install NEW O-ring seals (4) to the spray tip end of each fuel injector.
3. Lubricate the NEW lower injector O-ring seals with clean engine oil.
4. Install the fuel rail.
5. Install the fuel rail studs (1). Tighten: Tighten the studs to 10 N.m (89 lb in).
6. Install the fuel rail bracket retainer nut (2). Tighten: Tighten the nut to 10 N.m (89 lb in).
7. Position the harness over the engine.
8. Install the engine harness clip (2) to the fuel rail stud.
9. Connect the engine harness electrical connectors (1) to the rear fuel injectors.
10. Connect the engine harness electrical connectors (3) to the front fuel injectors.
11. Connect the engine harness electrical connector (1) to the starter solenoid cable electrical connector.
12. Install the surge tank inlet pipe to the fuel rail studs.
13. Install the surge tank inlet pipe nuts.
14. Install the surge tank inlet pipe hose to the engine fitting.
15. Position the surge tank inlet pipe hose clamp at the engine fitting.
16. Install the surge tank inlet pipe hose to the surge tank.
17. Position the surge tank inlet pipe hose clamp at the surge tank.
18. Connect the PCV air tube quick connect fitting to the camshaft cover. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
19. Connect the fuel feed pipe quick connect fitting (1) to the fuel rail. Refer to «Metal Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
20. Connect the negative battery cable. Refer to «Battery Negative Cable Disconnection and Connection»(/cadillac/dts/i-2005-2011/remont/charging-system/#battery-charging-system-and-starting-system) .
21. Inspect for fuel leaks using the following procedures: Turn ON the ignition, with the engine OFF for 2 seconds. Turn OFF the ignition for 10 seconds. Turn ON the ignition, with the engine OFF. Inspect for fuel leaks.
22. Install the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .

1. Remove the evaporative emission (EVAP) canister. Refer to «Evaporative Emission Canister Replacement»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
2. Place the EVAP canister on a suitable work surface.
3. Rotate the EVAP canister vent solenoid valve counterclockwise.
4. Remove the EVAP canister vent solenoid valve.

1. Install the EVAP canister vent solenoid valve.
2. Rotate the EVAP canister vent solenoid valve clockwise until the solenoid valve comes to a stop in the retainer.
3. Install the evaporative emission (EVAP) canister. Refer to «Evaporative Emission Canister Replacement»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .

1. Remove the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .
2. Disconnect the evaporative emission (EVAP) pipe (2) quick connect fitting from the EVAP canister purge solenoid valve. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
3. Disconnect the engine harness electrical connector (1) from EVAP canister purge solenoid valve.
4. Remove the EVAP canister purge solenoid valve bolt.
5. Remove the EVAP canister purge solenoid valve.

1. Install the EVAP canister purge solenoid valve.
2. Install the EVAP canister purge solenoid valve bolt. Tighten: Tighten the bolt to 10 N.m (89 lb ft).
3. Connect the engine harness electrical connector (1) to EVAP canister purge solenoid valve.
4. Connect the EVAP pipe (2) quick connect fitting to the EVAP canister purge solenoid valve. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
5. Install the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .

1. Remove the fuel rail. Refer to «Fuel Injection Fuel Rail Assembly Replacement»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
2. Remove the fuel injector fuel rail clip (1).
3. Remove the fuel injector (3).
4. Remove and discard the fuel injector upper (2) and lower (4) O-ring seals.

1. Lubricate the NEW O-rings seals with clean engine oil.
2. Install the NEW upper (2) and lower (4) injector O-rings seal onto the fuel injector.
3. Install the fuel injector (3) into the fuel rail.
4. Install the fuel injector fuel rail clip (1).
5. Install the fuel rail. Refer to «Fuel Injection Fuel Rail Assembly Replacement»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .

1. Relieve the fuel system pressure. Refer to «Fuel Pressure Relief (With CH 48027)»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) or «Fuel Pressure Relief (Without CH 48027)»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2__fuel-pressure-relief-without-ch-48027) .
2. Clean the fuel and evaporative emission (EVAP) pipe connections and areas surrounding the connections prior to disconnecting the connections in order to avoid possible contamination of the fuel and/or EVAP system.
3. Disconnect the fuel feed pipe (1) quick connect fitting at the fuel rail. Refer to «Metal Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
4. Disconnect the EVAP line (2) quick connect fitting at the EVAP canister purge valve. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
5. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/dts/i-2005-2011/remont/hoistjack/#general-information__lifting-jacking-the-vehicle) .
6. Loosen the fuel/EVAP pipe retainer bolt (1).
7. Disconnect the fuel feed rear pipe quick connect fitting (1) from the chassis fuel line. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
8. Disconnect the chassis EVAP line quick connect fitting (1) from the EVAP canister. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
9. Drill out the rivets (5) securing the retainer (2) to the underbody.
10. Disconnect the retainers (3, 4 and 1) from the underbody.
11. Remove the fuel/EVAP lines from the vehicle and place on a suitable work surface.
12. Remove the EVAP line from the retainers.

1. Install the EVAP line to the retainers.
2. Position the fuel/EVAP lines to the vehicle underbody.
3. Connect the retainers (3, 4 and 1) to the underbody.
4. Install NEW rivets (5) securing the retainer (2) to the underbody
5. Connect the chassis EVAP line quick connect fitting (1) to the EVAP canister. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
6. Connect the fuel feed rear pipe quick connect fitting (1) to the chassis fuel line. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
7. Position the retainer to the front of dash.
8. Tighten the fuel/EVAP pipe retainer bolt (1). Tighten: Tighten the bolt to 6 N.m (53 lb in).
9. Lower the vehicle.
10. Connect the EVAP line (2) quick connect fitting at the EVAP canister purge valve. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
11. Connect the fuel feed pipe (1) quick connect fitting at the fuel rail. Refer to «Metal Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
12. Connect the negative battery cable. Refer to «Battery Negative Cable Disconnection and Connection»(/cadillac/dts/i-2005-2011/remont/charging-system/#battery-charging-system-and-starting-system) .
13. Perform the following procedure in order to inspect for leaks: Turn ON the ignition, with the engine OFF for 2 seconds. Turn OFF the ignition for 10 seconds. Turn ON the ignition, with the engine OFF. Inspect for fuel leaks.
14. Install the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .

1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/dts/i-2005-2011/remont/hoistjack/#general-information__lifting-jacking-the-vehicle) .
2. Disconnect the chassis EVAP pipe quick connect fitting (1) from the EVAP canister. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
3. Disconnect the fuel tank vapor line quick connect fitting (3) from the EVAP canister. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
4. Disconnect the fuel fill pipe vent line quick connect fitting (2) from the EVAP canister. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
5. Remove the EVAP canister nuts.
6. Lower the EVAP canister until the EVAP canister vent solenoid valve electrical connector can be disconnected.
7. Disconnect the rear body harness electrical connector from the EVAP canister vent solenoid.
8. Remove the EVAP canister.
9. Place the EVAP canister on a suitable work surface.
10. Rotate the EVAP canister vent solenoid valve counterclockwise.
11. Remove the EVAP canister vent solenoid valve.

1. Install the EVAP canister vent solenoid valve to the new canister.
2. Rotate the EVAP canister vent solenoid valve clockwise until the solenoid valve comes to a stop in the retainer.
3. Place the EVAP canister near the underbody.
4. Connect the rear body harness electrical connector to the EVAP canister vent solenoid.
5. Install the EVAP canister onto the studs.
6. Install the EVAP canister nuts. Tighten: Tighten the nuts to 6 N.m (53 lb in).
7. Connect the fuel fill pipe vent line quick connect fitting (2) to the EVAP canister. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
8. Connect the fuel tank vapor line quick connect fitting (3) to the EVAP canister. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
9. Connect the chassis EVAP pipe quick connect fitting (1) to the EVAP canister. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
10. Lower the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/dts/i-2005-2011/remont/hoistjack/#general-information__lifting-jacking-the-vehicle) .

1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/dts/i-2005-2011/remont/hoistjack/#general-information__lifting-jacking-the-vehicle) .
2. Disconnect the fuel fill pipe vent hose quick connect fitting (3) at the evaporative emission (EVAP) canister. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
3. Using a 90 degree pick or an small flat-bladed screwdriver disengage the canister filter cover clips.
4. Remove and discard the EVAP canister filter cover (3).
5. Remove and discard the EVAP canister filter cover seal (2).
6. Remove and discard the EVAP canister filter (1).
7. Clean the inside of the EVAP canister filter housing with a clean shop towel.

1. Install a NEW EVAP canister filter (1) into the EVAP canister.
2. Install a NEW EVAP canister filter cover seal (2) to the NEW EVAP canister cover (3).
3. Snap the EVAP canister filter cover onto the EVAP canister.
4. Connect the fuel fill pipe vent hose quick connect fitting (3) at the EVAP canister. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
5. Lower the vehicle.

J 41413-200 EVAP Pressure and Purge Station. See Special Tools .

Inspection Procedure

Note. Use the EVAP Pressure/Purge Diagnostic Station J 41413 in order to provide a clean, dry, low pressure gas source. Do not substitute any other pressurized gas source. Damage may result to the EVAP system.

1. Turn OFF the ignition.
2. Remove the evaporative emission (EVAP) canister purge solenoid valve. Refer to «Evaporative Emission Canister Purge Solenoid Valve Replacement»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
3. Lightly tap the EVAP canister purge valve on a clean hard surface.
4. Inspect for carbon particles exiting either of the vacuum ports. If no carbon particles are found reinstall the EVAP canister purge valve and continue with the EVAP cleaning procedure. If you were instructed to replace the EVAP canister purge valve, and no carbon particles are found, return to the EVAP diagnostic procedure. Do not perform the EVAP cleaning procedure.

Cleaning Procedure

1. Remove the EVAP canister. Refer to «Evaporative Emission Canister Replacement»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
2. Turn OFF the main valve on the J 41413-200 . See «Special Tools»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
3. Disconnect the hose from the diagnostic station pressure regulator.
4. Using a section of vacuum hose, connect one end to the diagnostic station pressure regulator.
5. Connect the other end of the vacuum hose to the canister side of the EVAP purge pipe.
6. Turn on the main nitrogen cylinder valve and continue to discharge nitrogen for 15 seconds.
7. If the EVAP purge pipe is plugged and the nitrogen does not dislodge the carbon particles, replace the EVAP purge pipe. Refer to «Evaporative Emission Hoses/Pipes Replacement - Engine/Chassis»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
8. Return the EVAP Pressure/Purge Diagnostic Station to its original condition.
9. Install a new EVAP canister. Refer to «Evaporative Emission Canister Replacement»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
10. Lower the vehicle.
11. Continue with the published service manual diagnostic DTC procedure.

1. Remove both of the fuel injector sight shields. Refer to «Fuel Injector Sight Shield Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .
2. If servicing the ignition coil assembly, perform the following steps, if servicing an individual ignition coil proceed to step 7.
3. Disconnect the engine harness electrical connector (4) from the ignition coil assembly.
4. Remove the fuel injector sight shield studs.
5. Remove the ignition coil assembly bolts.
6. Remove the ignition coil assembly.
7. Disconnect the individual ignition coil electrical connector (3), as required.
8. Remove the individual ignition coil bolt (1), as required.
9. Remove the ignition coil (2), as required.

1. If servicing the ignition coil assembly, perform the following steps, if servicing an individual ignition coil proceed to step 6.
2. Install the ignition coil assembly.
3. Install the ignition coil assembly bolts. Tighten: Tighten the bolts to 10 N.m (89 lb in).
4. Install the fuel injector sight shield studs. Tighten: Tighten the studs to 10 N.m (89 lb in).
5. Connect the engine harness electrical connector (4) to the ignition coil assembly.
6. Install the ignition coil (2), as required.
7. Install the individual ignition coil bolt (1), as required. Tighten: Tighten the bolt to 10 N.m (89 lb in).
8. Connect the individual ignition coil electrical connector (3), as required.
9. Install both of the fuel injector sight shields. Refer to «Fuel Injector Sight Shield Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .

1. Remove the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .
2. If servicing the ignition coil assembly, perform the following steps, if servicing an individual ignition coil proceed to step 7.
3. Disconnect the engine harness electrical connector (3) from the ignition coil assembly.
4. Remove the ignition coil assembly bolts.
5. Remove the ignition coil assembly.
6. Disconnect the individual ignition coil electrical connector (3), as required.
7. Remove the individual ignition coil bolt (1), as required.
8. Remove the ignition coil (2), as required.

1. If servicing the ignition coil assembly, perform the following steps, if servicing an individual ignition coil proceed to step 5.
2. Install the ignition coil assembly.
3. Install the ignition coil assembly bolts. Tighten: Tighten the bolts to 10 N.m (89 lb in).
4. Connect the engine harness electrical connector (3) to the ignition coil assembly.
5. Install the ignition coil (2), as required.
6. Install the individual ignition coil bolt (1), as required. Tighten: Tighten the bolt to 10 N.m (89 lb in).
7. Connect the individual ignition coil electrical connector (3), as required.
8. Install the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .

Spark Plug Inspection

Spark Plug Usage

1. Ensure that the correct spark plug is installed. An incorrect spark plug causes driveability conditions. Refer to «Ignition System Specifications»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2__ignition-system-specifications) for the correct spark plug.
2. Ensure that the spark plug has the correct heat range. An incorrect heat range causes the following conditions: Spark plug fouling-Colder plug Pre-ignition causing spark plug and/or engine damage-Hotter plug

Spark Plug Inspection

1. Inspect the terminal post (1) for damage. Inspect for a bent or broken terminal post (1). Test for a loose terminal post (1) by twisting and pulling the post. The terminal post (1) should NOT move.
2. Inspect the insulator (2) for flashover or carbon tracking, soot. This is caused by the electrical charge traveling across the insulator (2) between the terminal post (1) and ground. Inspect for the following conditions: Inspect the spark plug boot for damage. Inspect the spark plug recess area of the cylinder head for moisture, such as oil, coolant, or water. A spark plug boot that is saturated causes arcing to ground.
3. Inspect the insulator (2) for cracks. All or part of the electrical charge may arc through the crack instead of the electrodes (3, 4).
4. Inspect (3) for evidence of improper arcing. Measure the gap between the center electrode (4) and the side electrode (3) terminals. Refer to «Ignition System Specifications»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2__ignition-system-specifications) . An excessively wide electrode gap can prevent correct spark plug operation. Inspect for the correct spark plug torque. Refer to «Ignition System Specifications»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2__ignition-system-specifications) . Insufficient torque can prevent correct spark plug operation. An over torqued spark plug, causes the insulator (2) to crack. Inspect for signs of tracking that occurred near the insulator tip instead of the center electrode (4). Inspect for a broken or worn side electrode (3). Inspect for a broken, worn, or loose center electrode (4) by shaking the spark plug. A rattling sound indicates internal damage. A loose center electrode (4) reduces the spark intensity. Inspect for bridged electrodes (3, 4). Deposits on the electrodes (3, 4) reduce or eliminates the gap. Inspect for worn or missing platinum pads on the electrodes (3, 4), if equipped. Inspect for excessive fouling.
5. Inspect the spark plug recess area of the cylinder head for debris. Dirty or damaged threads can cause the spark plug not to seat correctly during installation.

Spark Plug Visual Inspection

1. Normal operation-Brown to grayish-tan with small amounts of white powdery deposits are normal combustion by-products from fuels with additives.
2. Carbon fouled-Dry, fluffy black carbon, or soot caused by the following conditions: Rich fuel mixtures Leaking fuel injectors Excessive fuel pressure Restricted air filter element Incorrect combustion Reduced ignition system voltage output Weak coils Worn ignition wires Incorrect spark plug gap Excessive idling or slow speeds under light loads can keep spark plug temperatures so low that normal combustion deposits may not burn off.
3. Deposit fouling-Oil, coolant, or additives that include substances such as silicone, very white coating, reduces the spark intensity. Most powdery deposits will not effect spark intensity unless they form into a glazing over the electrode.

1. Remove the appropriate ignition coil. Refer to «Ignition Coil Replacement - Bank 2»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) or «Ignition Coil Replacement - Bank 1»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
2. Remove the spark plug(s) from the engine.
3. Inspect the spark plugs. Refer to «Spark Plug Inspection»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2__spark-plug-inspection) .

Note. Use only the spark plugs specified for use in the vehicle. Do not install spark plugs that are either hotter or colder than those specified for the vehicle. Installing spark plugs of another type can severely damage the engine.

Note. Check the gap of all new and reconditioned spark plugs before installation. The pre-set gaps may have changed during handling. Use a round feeler gauge to ensure an accurate check. Installing the spark plugs with the wrong gap can cause poor engine performance and may even damage the engine.

1. Measure the spark plug gap on the spark plug(s) to be installed. Compare the measurement to the gap specifications. Refer to «Ignition System Specifications»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2__ignition-system-specifications) , correct as necessary.
2. Install the spark plug(s) to the engine. Tighten: Tighten the plug(s) to 15 N.m (11 lb ft).
3. Install the appropriate ignition coil. Refer to «Ignition Coil Replacement - Bank 2»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) or «Ignition Coil Replacement - Bank 1»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .

1. Disconnect the engine harness electrical connector (1) from the crankshaft position (CKP) sensor wiring harness electrical connector.
2. Remove the intake manifold. Refer to «Intake Manifold Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .
3. Disconnect the CKP sensor wiring harness electrical connector (1) from the CKP sensor.
4. Disconnect the CKP sensor wiring harness electrical connector (2) from the left knock sensor.
5. Disconnect the harness clip (3) from the engine harness ground bracket.
6. Disconnect the CKP sensor wiring harness electrical connector (3) from the right knock sensor.
7. Remove the harness clip (4) from the engine block hole.
8. Remove the CKP sensor wiring harness bolts (1, 2).
9. Remove the CKP sensor wiring harness.

1. Install the CKP sensor wiring harness.
2. Install the CKP sensor wiring harness bolts (1, 2). Tighten: Tighten the bolt (1) to 10 N.m (89 lb in). Tighten the bolt (2) to 20 N.m (15 lb ft).
3. Install the harness clip (4) to the engine block hole.
4. Connect the CKP sensor wiring harness electrical connector (3) to the right knock sensor.
5. Connect the harness clip (3) to the engine harness ground bracket.
6. Connect the CKP sensor wiring harness electrical connector (2) to the left knock sensor.
7. Connect the CKP sensor wiring harness electrical connector (1) to the CKP sensor.
8. Install the intake manifold. Refer to «Intake Manifold Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .
9. Connect the engine harness electrical connector (1) to the CKP sensor wiring harness electrical connector.

1. Remove the intake manifold. Refer to «Intake Manifold Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .
2. Disconnect the crankshaft position (CKP) sensor wiring harness electrical connector (1) from the CKP sensor.
3. Remove the CKP sensor bolt. (cylinder heads shown removed, for clarity).
4. Remove the CKP sensor.

1. Lubricate the crankshaft sensor O-ring seal with clean engine oil.
2. Install the CKP sensor.
3. Install the CKP sensor bolt. Tighten: Tighten the bolt to 10 N.m (89 lb in).
4. Connect the CKP sensor wiring harness electrical connector (1) to the CKP sensor.
5. Install the intake manifold. Refer to «Intake Manifold Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .
6. Perform the CKP system variation learn procedure. Refer to «Crankshaft Position System Variation Learn»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2__crankshaft-position-system-variation-learn) .

1. Disconnect the electrical connector (1) from the camshaft position (CMP) sensor.
2. Remove the CMP sensor bolt.
3. Remove the CMP sensor.

1. Lubricate the CMP sensor O-ring seal with clean engine oil.
2. Install the CMP sensor.
3. Install the CMP sensor bolt. Tighten: Tighten the bolt to 10 N.m (89 lb in).
4. Connect the electrical connector (1) to the CMP sensor.

1. Remove the intake manifold. Refer to «Intake Manifold Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .
2. Disconnect the electrical connector (3) from the right knock sensor, if required.
3. Disconnect the electrical connector (2) from the left knock sensor, if required.
4. Remove the appropriate knock sensor. Cylinder heads shown removed for clarity.

1. Install the appropriate knock sensor. Tighten: Tighten the sensor to 25 N.m (18 lb ft).
2. Connect the electrical connector (2) to the left knock sensor, if required.
3. Connect the electrical connector (3) to the right knock sensor, if required.
4. Install the intake manifold. Refer to «Intake Manifold Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .

1. Remove the front air deflector. Refer to «Front Air Deflector Replacement»(/cadillac/dts/i-2005-2011/remont/exterior-body-panels/#bumper-system-fascia) .
2. Disconnect the engine harness electrical connector (1) from the secondary air injection (AIR) pump.
3. Disconnect the AIR pump inlet hose quick connect fitting from the AIR pump. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
4. Disconnect the AIR pump outlet hose quick connect fitting from the AIR pump. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
5. Remove the AIR pump bolt.
6. Loosen the AIR pump nuts.
7. Lift up and pull out in order to remove the AIR pump from the cradle bracket.

1. Align and install the AIR pump integral nuts to the holes in the cradle bracket and push the pump down.
2. Tighten the AIR pump nuts. Tighten: Tighten the nuts to 10 N.m (89 lb in).
3. Install the AIR pump bolt. Tighten: Tighten the bolt to 12 N.m (106 lb in).
4. Connect the AIR pump outlet hose quick connect fitting to the AIR pump. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
5. Connect the AIR pump inlet hose quick connect fitting to the AIR pump. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
6. Connect the engine harness electrical connector (1) to the AIR pump.
7. Install the front air deflector. Refer to «Front Air Deflector Replacement»(/cadillac/dts/i-2005-2011/remont/exterior-body-panels/#bumper-system-fascia) .

1. Remove the front air deflector. Refer to «Front Air Deflector Replacement»(/cadillac/dts/i-2005-2011/remont/exterior-body-panels/#bumper-system-fascia) .
2. Disconnect the secondary air injection (AIR) pump inlet hose quick connect fitting from the AIR pump. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
3. Lower the vehicle.
4. Disconnect the AIR pump inlet hose quick connect fitting from the air cleaner. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
5. Remove the AIR pump inlet hose from the vehicle.

1. Install the AIR pump inlet hose from the vehicle.
2. Connect the AIR pump inlet hose quick connect fitting to the air cleaner. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
3. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/dts/i-2005-2011/remont/hoistjack/#general-information__lifting-jacking-the-vehicle) .
4. Connect the AIR pump inlet hose quick connect fitting to the AIR pump. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
5. Install the front air deflector. Refer to «Front Air Deflector Replacement»(/cadillac/dts/i-2005-2011/remont/exterior-body-panels/#bumper-system-fascia) .

1. Remove the air deflector. Refer to «Front Air Deflector Replacement»(/cadillac/dts/i-2005-2011/remont/exterior-body-panels/#bumper-system-fascia) .
2. Disconnect the secondary air injection (AIR) pump outlet hose quick connect fitting from the AIR pump. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
3. Open and slide down the pinch clamp attaching the AIR hose to the AIR pipe.
4. Separate the AIR hose from the AIR pipe.
5. Remove the retainers attaching the AIR hose to the engine cradle.
6. Remove the AIR hose from the vehicle.
7. Lower the vehicle.
8. Remove the heated oxygen sensor (HO2S) clip (5) from the AIR pipe bracket.
9. Pinch the constant tension clamp and remove the AIR pipe from the check valve.
10. Remove the AIR pipe nuts (2, 3).
11. Remove the AIR pipe.

1. Install the AIR pipe.
2. Connect the AIR pipe to the check valve.
3. Install the AIR pipe nuts (2, 3). Tighten: Tighten the nuts to 9 N.m (80 lb in).
4. Install the HO2S clip (5) to the AIR pipe bracket.
5. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/dts/i-2005-2011/remont/hoistjack/#general-information__lifting-jacking-the-vehicle) .
6. Install and position the AIR hose to the cradle.
7. Install the retainers attaching the AIR hose to the engine cradle.
8. Install the AIR hose to the AIR pipe.
9. Open and slide into position the pinch clamp attaching the AIR hose to the AIR pipe.
10. Connect the AIR pump outlet hose quick connect fitting to the AIR pump. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
11. Install the air deflector. Refer to «Front Air Deflector Replacement»(/cadillac/dts/i-2005-2011/remont/exterior-body-panels/#bumper-system-fascia) .

1. Remove the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .
2. Disconnect the engine harness electrical connector (4) from the secondary air injection (AIR) check valve.
3. Pinch the constant tension clamp (1) and remove the AIR pipe from the AIR check valve.
4. Remove the AIR check valve to exhaust manifold nuts (3).
5. Remove the AIR check valve bolts (1).
6. Remove the AIR check valve.
7. Remove and discard the AIR check valve to exhaust manifold gasket (4).
8. Clean the AIR to exhaust manifold gasket sealing surfaces.

1. Install a NEW AIR check valve to exhaust manifold gasket (4).
2. Install the AIR check valve.
3. Install the AIR check valve to exhaust manifold nuts (3). Tighten: Tighten the nuts to 9 N.m (80 lb in).
4. Install the AIR check valve bolts (1). Tighten: Tighten the bolts to 9 N.m (80 lb in).
5. Connect the AIR pipe to the AIR check valve.
6. Connect the engine harness electrical connector (4) to the AIR check valve.
7. Install the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .

1. Remove the fuel injector sight shield, if necessary. Refer to «Fuel Injector Sight Shield Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .
2. Disconnect the engine harness electrical connector (2) from the exhaust gas recirculation (EGR) valve.
3. Remove the EGR bracket shield nuts.
4. Remove the EGR bracket shield.
5. Remove the EGR valve bolts.
6. Remove the EGR valve.
7. Remove and discard the EGR valve gasket.
8. Clean the EGR valve mounting surface.

1. Install a NEW EGR gasket.
2. Install the EGR valve.
3. Install the EGR valve bolts. Tighten: Tighten the bolts to 24 N.m (18 lb ft).
4. Install the EGR bracket shield.
5. Install the EGR bracket shield nuts. Tighten: Tighten the nuts to 10 N.m (89 lb in).
6. Connect the engine harness electrical connector (2) to the EGR valve.
7. Install the fuel injector sight shield, if necessary. Refer to «Fuel Injector Sight Shield Replacement»(/cadillac/dts/i-2005-2011/remont/mechanical/#engine-mechanical-46l-2-of-5) .

1. Remove the EGR pipe bolt at the water pump housing.
2. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/dts/i-2005-2011/remont/hoistjack/#general-information__lifting-jacking-the-vehicle) .
3. Loosen the EGR pipe nut at the exhaust manifold.
4. Remove the EGR valve pipe.

1. Position the EGR valve pipe to the exhaust manifold.
2. Tighten the EGR pipe nut at the exhaust manifold. Tighten: Tighten the nut to 60 N.m (44 lb ft).
3. Lower the vehicle.
4. Install the EGR valve pipe bolt at the water pump housing. Tighten: Tighten the bolt to 28 N.m (21 lb ft).

Exhaust Gas Recirculation (EGR) System Cleaning

Whenever the exhaust gas recirculation (EGR) valve is removed the EGR system should be inspected and cleaned if necessary. This will ensure that the EGR system will function properly under all operating conditions. Proper EGR system service consists of the following 5 steps

1. EGR system diagnosis - Diagnosis of the EGR system should be performed if PCM DTCs are set.
2. EGR valve pipe cleaning and checking for leaks - Clean and check the EGR pipe from the exhaust manifold to the EGR valve and the EGR pipe from the water pump crossover to the throttle body spacer. Refer to «Exhaust Gas Recirculation Pipe Replacement»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
3. EGR valve cleaning - If the EGR system is operating correctly, the EGR valve can be removed, checked for deposits, cleaned, and re-installed. Use the procedure below for this operation. Remove the EGR valve. Refer to «Exhaust Gas Recirculation Valve Replacement»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) . While holding the EGR valve in your hand, use a pencil eraser or other suitable soft instrument to depress the pintle several times. The pintle should move in and out smoothly. Replace any valve that exhibits tendencies to stick. While holding the EGR valve base in your hand, try to rotate the connector housing. Repeat for the coil housing. Replace any valve that exhibits looseness. Inspect the EGR valve pintle and seat for deposits. Use a cloth or other suitable soft device to remove deposits. Remove all loose particles. If the deposits are such that pintle/base interface cannot be cleaned adequately to allow the pintle to seal against the seat, replace the valve. Damage to the powdered metal EGR valve base will occur if cleaned with solvents, sharp tools, a wire brush or wheel, or by sand blasting. Cleaning by these methods is not recommended. Inspect the passage in the water crossover assembly for deposits. Remove all loose particles. Install the EGR valve on the engine using a NEW gasket. Refer to «Exhaust Gas Recirculation Valve Replacement»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
4. Cleaning the EGR passages in the water crossover assembly. Remove the water pump housing. Refer to «Engine Coolant Crossover Pipe Replacement»(/cadillac/dts/i-2005-2011/remont/cooling-system-mechanical/#engine-cooling-system) . Remove the 2 plugs (2) and clean the passages with a wire brush. Remove all loose particles. Install the water pump housing. Refer to «Engine Coolant Crossover Pipe Replacement»(/cadillac/dts/i-2005-2011/remont/cooling-system-mechanical/#engine-cooling-system) .
5. Wash-up with soap and water after any contact with deposits from the EGR system.

1. Loosen the air cleaner cover screws (1).
2. Open the air cleaner cover.
3. Remove the air filter from the air cleaner.
4. Inspect the air cleaner housing assembly for damage. If a problem is found, replace as necessary.

1. Install the air filter to the air cleaner.
2. Close the air cleaner cover. Ensure that the inboard hinges are engaged prior to tightening the screws.
3. Tighten the air cleaner cover screws (1). Tighten: Tighten the screws to 3 N.m (27 lb in).

1. Disconnect the engine harness electrical connector from the mass air flow (MAF)/intake air temperature (IAT) sensor.
2. Disconnect the positive crankcase ventilation (PCV) fresh air tube quick connect fitting from the air cleaner outlet duct. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
3. Disconnect the secondary air injection (AIR) pump inlet hose quick connect fitting from the air cleaner. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
4. Loosen the air cleaner outlet duct clamp at the throttle body.
5. Remove the air cleaner outlet duct from the throttle body.
6. Disengage the 3 integral clips (1) on the lower housing from the upper housing.
7. Remove the air cleaner upper housing.
8. If replacing the air cleaner lower housing also, perform the following steps if not proceed to step 11.
9. Remove the engine harness and engine control module (ECM) from the lower housing.
10. Pull up firmly on the lower housing in order to disengage the grommets from the studs. Remove the air cleaner lower housing.
11. If replacing the air cleaner upper housing only perform the following steps, loosen the air cleaner outlet duct clamp at the MAF/IAT sensor.
12. Remove the air cleaner outlet duct.
13. Remove the MAF/IAT sensor bolts.
14. Remove the MAF/IAT sensor.

1. If the upper air cleaner housing was replaced only perform the following steps otherwise proceed to step 6.
2. Install the MAF/IAT sensor.
3. Install the MAF/IAT sensor bolts. Tighten: Tighten the bolts to 4 N.m (35 lb ft).
4. Install the air cleaner outlet duct.
5. Tighten the air cleaner outlet duct clamp at the MAF/IAT sensor. Tighten: Tighten the clamp to 4 N.m (35 lb in).
6. Place the lower air cleaner housing over the studs and push down firmly in order to engage the grommets to the studs.
7. Install the engine harness and ECM to the lower housing.
8. Install the air cleaner upper housing.
9. engage the 3 integral clips (1) on the lower housing to the upper housing.
10. Install the air cleaner outlet duct to the throttle body.
11. Tighten the air cleaner outlet duct clamp at the throttle body. Tighten: Tighten the clamp to 4 N.m (35 lb in).
12. Connect the AIR pump inlet hose quick connect fitting to the air cleaner. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
13. Connect the PCV fresh air tube quick connect fitting to the air cleaner outlet duct. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
14. Connect the engine harness electrical connector to the MAF/IAT sensor.

1. Disconnect the engine harness electrical connector from the mass air flow (MAF)/intake air temperature (IAT) sensor.
2. Disconnect the positive crankcase ventilation (PCV) fresh air tube quick connect fitting from the air cleaner outlet duct. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
3. Loosen the air cleaner outlet duct clamp at the throttle body.
4. Remove the air cleaner outlet duct from the throttle body.
5. Loosen the air cleaner outlet duct from the MAF/IAT sensor.
6. Remove the air cleaner outlet duct from the MAF/IAT sensor and the vehicle.

1. Install air cleaner outlet duct to the vehicle and the MAF/IAT sensor.
2. Tighten the air cleaner outlet duct clamp at the MAF/IAT sensor. Tighten: Tighten the clamp to 4 N.m (35 lb in).
3. Install the air cleaner outlet duct to the throttle body.
4. Tighten the air cleaner outlet duct clamp at the throttle body. Tighten: Tighten the clamp to 4 N.m (35 lb in).
5. Connect the PCV fresh air tube quick connect fitting to the air cleaner outlet duct. Refer to «Plastic Collar Quick Connect Fitting Service»(/cadillac/dts/i-2005-2011/remont/testing-diagnostics/#engine-control-system-fuel-system-46l-introduction-2-of-2) .
6. Connect the engine harness electrical connector to the MAF/IAT sensor.

Electronic Ignition (EI) System Operation

The electronic ignition (EI) system produces and controls the high energy secondary spark. This spark ignites the compressed air/fuel mixture at precisely the correct time, providing optimal performance, fuel economy, and control of exhaust emissions. The engine control module (ECM) primarily collects information from the crankshaft position (CKP) and camshaft position (CMP) sensors to control the sequence, dwell, and timing of the spark.

Crankshaft Position (CKP) Sensor

The crankshaft position (CKP) sensor circuits consist of an engine control module (ECM) supplied 5-volt reference circuit, a low reference circuit, and an output signal circuit. The CKP sensor is an internally magnetic biased digital output integrated circuit sensing device. The sensor detects magnetic flux changes of the teeth and slots of a 58-tooth reluctor wheel on the crankshaft. Each tooth on the reluctor wheel is spaced at 60-tooth spacing, with 2 missing teeth for the reference gap. The CKP sensor produces an ON/OFF DC voltage of varying frequency, with 58 output pulses per crankshaft revolution. The frequency of the CKP sensor output depends on the velocity of the crankshaft. The CKP sensor sends a digital signal, which represents an image of the crankshaft reluctor wheel, to the ECM as each tooth on the wheel rotates past the CKP sensor. The ECM uses each CKP signal pulse to determine crankshaft speed and decodes the crankshaft reluctor wheel reference gap to identify crankshaft position. This information is then used to determine the optimum ignition and injection points of the engine. The ECM also uses CKP sensor output information to determine the camshaft relative position to the crankshaft, to control camshaft phasing, and to detect cylinder misfire.

Crankshaft Reluctor Wheel

The crankshaft reluctor wheel is part of the crankshaft. The reluctor wheel consists of 58 teeth and a reference gap. Each tooth on the reluctor wheel is spaced 6 degrees apart with a 12-degree space for the reference gap. The pulse from the reference gap is known as the sync pulse. The sync pulse is used to synchronize the coil firing sequence with the crankshaft position, while the other teeth provide cylinder location during a revolution.

Camshaft Position (CMP) Sensor

The camshaft position (CMP) sensor is triggered by a notched reluctor wheel built onto the exhaust camshaft sprocket. The CMP sensor provides four signal pulses every camshaft revolution. Each notch, or feature of the reluctor wheel is of a different size which is used to identify the compression stroke of each cylinder and to enable sequential fuel injection. The CMP sensor is connected to the engine control module (ECM) by the following circuits

1. A 5-volt reference circuit
2. A low reference circuit
3. A signal circuit

Ignition Coil/Module

Each ignition coil/module has the following circuits

1. An ignition voltage circuit
2. A ground
3. An ignition control (IC) circuit
4. A low reference circuit

The engine control module (ECM) controls the individual coils by transmitting timing pulses on the IC circuit of each ignition coil/module to enable a spark event.

The spark plugs are connected to each coil by a short boot. The boot contains a spring that conducts the spark energy from the coil to the spark plug. The spark plug electrode is tipped with platinum for long wear and higher efficiency.

Engine Control Module (ECM)

The engine control module (ECM) controls all ignition system functions, and constantly corrects the spark timing. The ECM monitors information from various sensor inputs that include the following

1. The throttle position (TP) sensor
2. The engine coolant temperature (ECT) sensor
3. The mass air flow (MAF) sensor
4. The intake air temperature (IAT) sensor
5. The vehicle speed sensor (VSS)
6. The engine knock sensor (KS)
7. The manifold absolute pressure (MAP) sensor

Modes of Operation

During normal operation the engine control module (ECM) controls all ignition functions. If either the crankshaft position (CKP) or camshaft position (CMP) sensor signal is lost, the engine will continue to run because the ECM will default to a limp home mode using the remaining sensor input. Each coil is internally protected against damage from excessive voltage. If one or more coils were to fail in this manner, a misfiring condition would result. Diagnostic trouble codes are available to accurately diagnose the ignition system with a scan tool.

Engine Control Module Description

The engine control module (ECM) interacts with many emission related components and systems, and monitors the emission related components and systems for deterioration. OBD II diagnostics monitor the system performance and a diagnostic trouble code (DTC) sets if the system performance degrades.

The malfunction indicator lamp (MIL) operation and the DTC storage are dictated by the DTC type. A DTC is ranked as a Type A or Type B if the DTC is emissions related. Type C is a non-emissions related DTC.

The ECM is in the engine compartment. The ECM is the control center of the engine controls system. The ECM controls the following components

1. The fuel injection system
2. The ignition system
3. The emission control systems
4. The on-board diagnostics
5. The A/C and fan systems
6. The throttle actuation control (TAC) system

The ECM constantly monitors the information from various sensors and other inputs, and controls the systems that affect the vehicle performance and the emissions. The ECM also performs diagnostic tests on various parts of the system. The ECM can recognize operational problems and alert the driver via the MIL. When the ECM detects a malfunction, the ECM stores a DTC. The condition area is identified by the particular DTC that is set. This aids the technician in making repairs.

ECM Function

The engine control module (ECM) can supply 5 volts or 12 volts to the various sensors or switches. This is done through pull-up resistors to the regulated power supplies within the ECM. In some cases, even an ordinary shop voltmeter will not give an accurate reading because the resistance is too low. Therefore, a DMM with at least 10 megaohms input impedance is required in order to ensure accurate voltage readings.

The ECM controls the output circuits by controlling the ground or the power feed circuit through the transistors or a device called an output driver module.

EEPROM

The electronically erasable programmable read only memory (EEPROM) is a permanent memory that is physically part of the engine control module (ECM). The EEPROM contains program and calibration information that the ECM needs in order to control the powertrain operation.

Special equipment, as well as the correct program and calibration for the vehicle, are required in order to reprogram the ECM.

Data Link Connector (DLC)

The data link connector (DLC) is a 16-pin connector that provides the technician a means of accessing serial data for aid in the diagnosis. This connector allows the technician to use a scan tool in order to monitor the various serial data parameters, and display the DTC information. The DLC is located inside of the drivers compartment, underneath the dash.

Malfunction Indicator Lamp (MIL) Operation

The malfunction indicator lamp (MIL) is located in the instrument panel cluster. The MIL will display as either SERVICE ENGINE SOON or one of the following symbols when commanded ON

Scheme 14

Scheme 15

The MIL indicates that an emissions related fault has occurred and vehicle service is required.

The following is a list of the modes of operation for the MIL

1. The MIL illuminates when the ignition is turned ON, with the engine OFF. This is a bulb test to ensure the MIL is able to illuminate.
2. The MIL turns OFF after the engine is started if a diagnostic fault is not present.
3. The MIL remains illuminated after the engine is started if the control module detects a fault. A diagnostic trouble code (DTC) is stored any time the control module illuminates the MIL due to an emissions related fault. The MIL turns OFF after three consecutive ignition cycles in which a Test Passed has been reported for the diagnostic test that originally caused the MIL to illuminate.
4. The MIL flashes if the control module detects a misfire condition which could damage the catalytic converter.
5. When the MIL is illuminated and the engine stalls, the MIL will remain illuminated as long as the ignition is ON.
6. When the MIL is not illuminated and the engine stalls, the MIL will not illuminate until the ignition is cycled OFF and then ON.

ECM Service Precautions

The engine control module (ECM), by design, can withstand the normal current draws that are associated with the vehicle operations. However, care must be used in order to avoid overloading any of these circuits. When testing for opens or shorts, do not ground or apply voltage to any of the ECM circuits unless the diagnostic procedure instructs you to do so. These circuits should only be tested with a DMM.

Emissions Diagnosis For State I/M Programs

This OBD II equipped vehicle is designed to diagnose any conditions that could lead to excessive levels of the following emissions

1. Hydrocarbons (HC)
2. Carbon monoxide (CO)
3. Oxides of nitrogen (NOx)
4. Evaporative emission (EVAP) system losses

Should this vehicles on-board diagnostic system (ECM) detect a condition that could result in excessive emissions, the ECM turns ON the malfunction indicator lamp (MIL) and stores a DTC that is associated with the condition.

Aftermarket (Add-On) Electrical & Vacuum Equipment

Note. Do not attach add-on vacuum operated equipment to this vehicle. The use of add-on vacuum equipment may result in damage to vehicle components or systems.

Note. Connect any add-on electrically operated equipment to the vehicle's electrical system at the battery (power and ground) in order to prevent damage to the vehicle.

Aftermarket, add-on, electrical and vacuum equipment is defined as any equipment installed on a vehicle after leaving the factory that connects to the vehicles electrical or vacuum systems. No allowances have been made in the vehicle design for this type of equipment.

Add-on electrical equipment, even when installed to these strict guidelines, may still cause the powertrain system to malfunction. This may also include equipment not connected to the vehicle electrical system, such as portable telephones and radios. Therefore, the first step in diagnosing any powertrain condition is to eliminate all of the aftermarket electrical equipment from the vehicle. After this is done, if the problem still exists, the problem may be diagnosed in the normal manner.

Electrostatic Discharge (ESD) Damage

The electronic components that are used in the control systems are often designed to carry very low voltage. The electronic components are susceptible to damage caused by electrostatic discharge. Less than 100 volts of static electricity can cause damage to some electronic components.

There are several ways for a person to become statically charged. The most common methods of charging are by friction and by induction. An example of charging by friction is a person sliding across a car seat.

Charging by induction occurs when a person with well insulated shoes stands near a highly charged object and momentarily touches ground. Charges of the same polarity are drained off leaving the person highly charged with the opposite polarity. Static charges can cause damage, therefore, it is important to use care when handling and testing electronic components.

Emissions Control Information Label

The underhood Vehicle Emissions Control Information Label contains important emission specifications and setting procedures. In the upper left corner is the exhaust emission information. This identifies the year, the manufacturing division of the engine, the displacement of the engine in liters, the class of the vehicle, and type of fuel metering system. There is also an illustrated emission components and vacuum hose schematic.

This label is located in the engine compartment of every General Motors vehicle. If the label has been removed, it can be ordered from GM service parts operations (GMSPO).

Underhood Inspection

Perform a careful underhood inspection when performing any diagnostic procedure or diagnosing the cause of an emission test failure. This can often lead to repairing a condition without further steps. Use the following guidelines when performing an inspection

1. Inspect all of the vacuum hoses for correct routing, pinches, cuts, or disconnects.
2. Inspect any hoses that are difficult to see.
3. Inspect all of the wires in the engine compartment for the following conditions: Burned or chafed spots Pinched wires Contact with sharp edges Contact with hot exhaust manifolds

EVAP System Operation

The evaporative emission (EVAP) control system limits fuel vapors from escaping into the atmosphere. Fuel tank vapors are allowed to move from the fuel tank, due to pressure in the tank, through the vapor pipe, into the EVAP canister. Carbon in the canister absorbs and stores the fuel vapors. Excess pressure is vented through the vent line and EVAP canister vent solenoid valve to atmosphere. The EVAP canister stores the fuel vapors until the engine is able to use them. At an appropriate time, the control module will command the EVAP canister purge solenoid valve ON, open, allowing engine vacuum to be applied to the EVAP canister. With the EVAP canister vent solenoid valve OFF, open, fresh air will be drawn through the solenoid valve and vent line to the EVAP canister. Fresh air is drawn through the canister, pulling fuel vapors from the carbon. The air/fuel vapor mixture continues through the EVAP purge pipe and EVAP canister purge solenoid valve into the intake manifold to be consumed during normal combustion. The control module uses several tests to determine if the EVAP system is leaking.

Large Leak Test

This tests for large leaks and blockages in the evaporative emission (EVAP) system. The control module will command the EVAP canister vent solenoid valve ON, closed, and command the EVAP canister purge solenoid valve ON, open, with the engine running, allowing engine vacuum into the EVAP system. The control module monitors the fuel tank pressure (FTP) sensor voltage to verify that the system is able to reach a predetermined level of vacuum within a set amount of time. The control module then commands the EVAP purge solenoid valve OFF, closed, sealing the system and monitors the vacuum level for decay. If the control module does not detect that the predetermined vacuum level was achieved, or the vacuum decay rate is more than a calibrated level on 2 consecutive tests, a DTC P0455 will set.

Small Leak Test

The engine off natural vacuum (EONV) diagnostic is the small leak diagnostic for the evaporative emission (EVAP) system. The EONV utilizes the dynamic temperature changes in the fuel tank immediately following a drive cycle to generate natural vacuum or pressure in the fuel tank. While previous leak detection was performed with the engine running, the EONV monitors the EVAP system with the key OFF. The control module will remain active for up to 45 minutes after the engine is turned OFF. The EONV test monitors the fuel tank pressure (FTP) or vacuum as the fuel changes temperature to determine if a leak is present. If the system is truly sealed, there will be a pressure and/or vacuum change as the temperature of the fuel changes. Pressure or vacuum changes that are less than the calibrated values indicate a leak. The EONV diagnostic is designed to detect leaks as small as 0.51 mm (0.02 inches). The procedure for locating and repairing the EVAP system leaks is the same for the EONV as with the other EVAP systems. If the test reports a falling value, DTC P0442 will set.

Canister Vent Restriction Test

If the evaporative emission (EVAP) vent system is restricted, fuel vapors will not be properly purged from the EVAP canister. The control module tests this by commanding the EVAP canister purge solenoid valve ON, open, and commanding the EVAP canister vent solenoid valve OFF, open, and monitoring the fuel tank pressure (FTP) sensor for an increase in vacuum. If vacuum increases more than a calibrated value, DTC P0446 will set.

EVAP Purge Solenoid Valve Leak Test

If the evaporative emission (EVAP) canister purge solenoid valve does not seal properly, fuel vapors could enter the engine at an undesired time, causing driveability concerns. The control module tests for this by commanding the EVAP canister purge solenoid valve OFF, closed, and EVAP canister vent solenoid valve ON, closed, sealing the system, and monitoring the fuel tank pressure (FTP) for an increase in vacuum. If the control module detects that EVAP system vacuum increases above a calibrated value, DTC P0496 will set.

Check Gas Cap Message

The powertrain control module (PCM) sends a class 2 message to the driver information center (DIC) illuminating the Check Gas Cap message when any of the following occur

1. A malfunction in the evaporative emission (EVAP) system and a large leak test fails
2. A malfunction in the EVAP system and a small leak test fails

EVAP System Components

The evaporative emission (EVAP) system consists of the following components

EVAP Canister

The canister is filled with carbon pellets used to absorb and store fuel vapors. Fuel vapor is stored in the canister until the control module determines that the vapor can be consumed in the normal combustion process.

EVAP Canister Purge Solenoid Valve

The EVAP canister purge solenoid valve controls the flow of vapors from the EVAP system to the intake manifold. This normally closed solenoid is pulse width modulated (PWM) by the control module to precisely control the flow of fuel vapor to the engine. The solenoid will also be opened during some portions of the EVAP testing, allowing engine vacuum to enter the EVAP system.

EVAP Canister Vent Solenoid Valve

The EVAP canister vent solenoid valve controls fresh airflow into the EVAP canister. The valve is normally open. The control module will command the solenoid closed during some EVAP tests, allowing the system to be tested for leaks.

Fuel Tank Pressure Sensor

The fuel tank pressure (FTP) sensor measures the difference between the pressure or vacuum in the fuel tank and outside air pressure. The control module provides a 5-volt reference and a ground to the FTP sensor. The FTP sensor provides a signal voltage back to the control module that can vary between 0.1-4.9 volts. As FTP increases, FTP sensor voltage decreases, high pressure = low voltage. As FTP decreases, FTP voltage increases, low pressure or vacuum = high voltage.

EVAP Service Port

The EVAP service port is located in the EVAP purge pipe between the EVAP canister purge solenoid valve and the EVAP canister. The service port is identified by a green colored cap.

Exhaust Gas Recirculation (EGR) System

The exhaust gas recirculation (EGR) system is used to reduce the amount of nitrogen oxide (NOx) emission levels caused by combustion temperatures exceeding 816°C (1,500°F). It does this by introducing small amounts of exhaust gas back into the combustion chamber. The exhaust gas absorbs a portion of the thermal energy produced by the combustion process and thus decreases combustion temperature. The EGR system will only operate under specific temperature, barometric pressure and engine load conditions in order to prevent driveability concerns and to increase engine performance.

Scheme 16

Linear EGR Control

The linear EGR valve is controlled by a high side driver within the engine control module (ECM). The high side driver provides 12 volts that is pulse width modulated (PWM) by a duty cycle via the high control circuit of the EGR valve. The ground path is provided by the low control circuit of the EGR valve. The ECM calculates the amount of EGR needed based on the following inputs

1. The engine coolant temperature (ECT) sensor
2. The intake air temperature (IAT) sensor
3. The barometric pressure (BARO)
4. The manifold absolute pressure (MAP) sensor
5. The throttle position (TP) sensor
6. The mass air flow (MAF) sensor

EGR Diagnostics

The engine control module (ECM) tests the EGR flow during deceleration by momentarily commanding the EGR valve to open while monitoring the signal of the manifold absolute pressure (MAP) sensor. When the EGR valve is opened, the ECM will expect to see a predetermined increase in MAP. If the expected increase in MAP is not detected, the ECM records the amount of MAP difference that was detected and adjusts a calibrated fail counter towards a calibrated fail threshold level. When the fail counter exceeds the fail threshold level, the ECM will set a diagnostic trouble code (DTC).

Normally, the ECM will only allow one EGR Flow Test Count during an ignition cycle. To aid in verifying a repair, the ECM allows twelve EGR Flow Test Counts during the first ignition cycle following a code clear or a battery disconnect. Between nine and twelve EGR Flow Test Counts should be sufficient for the ECM to determine adequate EGR flow and pass the EGR flow test. If the ECM detects an EGR flow error, a DTC will set.

The ECM monitors the position of the EGR valve pintle via the EGR position sensor. If the ECM detects a calibrated variance between the Desired EGR Position parameter and the EGR Position Sensor parameter, actual position, for a calibrated amount of time a DTC will set.

The ECM also monitors the EGR solenoid high control circuit EGR solenoid low control circuit for electrical faults. If an EGR control circuit fault is detected for a calibrated amount of time a DTC will set.

Fuel System Overview

The fuel system is a returnless on-demand design. The fuel pressure regulator is a part of the fuel sender assembly, eliminating the need for a return pipe from the engine. A returnless fuel system reduces the internal temperature of the fuel tank by not returning hot fuel from the engine to the fuel tank. Reducing the internal temperature of the fuel tank results in lower evaporative emissions.

An electric turbine style fuel pump attaches to the fuel sender assembly inside the fuel tank. The fuel pump supplies high pressure fuel through the fuel feed pipe to the fuel injection system. The fuel pump provides fuel at a higher rate of flow than is needed by the fuel injection system. The fuel pressure regulator, a part of the fuel sender assembly, maintains the correct fuel pressure to the fuel injection system. The fuel pump and sender assembly contains a reverse flow check valve. The check valve and the fuel pressure regulator maintain fuel pressure in the fuel feed pipe and the fuel rail in order to prevent long cranking times.

Scheme 17

The fuel tank stores the fuel supply. The fuel tank is located in the rear of the vehicle. The fuel tank is held in place by 2 metal straps that attach to the frame. The fuel tank is molded from high density polyethylene.

Fuel Fill Pipe

The fuel fill pipe has a built-in restrictor and deflector in order to prevent refueling with leaded fuel.

Scheme 18

Note. If a fuel tank filler cap requires replacement, use only a fuel tank filler cap with the same features. Failure to use the correct fuel tank filler cap can result in a serious malfunction of the fuel and EVAP system.

The fuel fill pipe has a tethered fuel filler cap (1). A torque-limiting device prevents the cap from being over tightened. To install the cap, turn the cap clockwise until you hear audible clicks. This indicates that the cap is correctly torqued and fully seated. A fuel filler cap that is not fully seated may cause a malfunction in the emission system.

Scheme 19

The fuel sender assembly consists of the following major components

1. The fuel tank pressure sensor (1)
2. The fuel tank fuel pump module (2)
3. The fuel level sensor (3)

Fuel Level Sensor

The fuel level sensor consists of a float, a wire float arm, and a ceramic resistor card. The position of the float arm indicates the fuel level. The fuel level sensor contains a variable resistor which changes resistance in correspondence with the position of the float arm. The control module sends the fuel level information via the GMLAN serial data circuit to the instrument panel cluster (IPC). This information is used for the IPC fuel gauge and the low fuel warning indicator, if applicable. The control module also monitors the fuel level input for various diagnostics.

Fuel Pump

The fuel pump is mounted in the fuel sender assembly reservoir. The fuel pump is an electric high-pressure pump. Fuel is pumped to the fuel injection system at a specified flow and pressure. The fuel pump delivers a constant flow of fuel to the engine even during low fuel conditions and aggressive vehicle maneuvers. The control module controls the electric fuel pump operation through a fuel pump relay. The fuel pump flex pipe acts to dampen the fuel pulses and noise generated by the fuel pump.

Fuel Strainer

The fuel strainer attaches to the lower end of the fuel sender. The fuel strainer is made of woven plastic. The functions of the fuel strainer are to filter contaminants and to wick fuel. The fuel strainer normally requires no maintenance. Fuel stoppage at this point indicates that the fuel tank contains an abnormal amount of sediment or contamination.

Scheme 20

The fuel pressure regulator (2) is contained in the fuel sender assembly near the fuel pump outlet. The fuel pressure regulator is a diaphragm relief valve. The diaphragm has fuel pressure on one side and regulator spring pressure on the other side. The fuel pressure regulator is not vacuum biased. Fuel pressure is controlled by a pressure balance across the regulator. The fuel system pressure is constant.

Fuel Feed Pipes

The fuel feed pipe carries fuel from the fuel tank to the fuel rail assembly. The fuel return pipe carries fuel from the fuel rail assembly back to the fuel tank. The fuel pipes consist of 2 sections

1. The rear fuel pipe assemblies are located from the top of the fuel tank to the chassis fuel pipes. The rear fuel pipes are constructed of nylon.
2. The chassis fuel pipes are located under the vehicle and connect the rear fuel pipes to the fuel rail pipes. These pipes are constructed of steel.

Nylon Fuel Pipes

Nylon pipes are constructed to withstand maximum fuel system pressure, exposure to fuel additives, and changes in temperature. Heat resistant rubber hose or corrugated plastic conduit protect the sections of the pipes that are exposed to chafing, high temperature, or vibration.

Nylon fuel pipes are somewhat flexible and can be formed around gradual turns under the vehicle. However, if nylon fuel pipes are forced into sharp bends, the pipes kink and restrict the fuel flow. Also, once exposed to fuel, nylon pipes may become stiffer and are more likely to kink if bent too far. Take special care when working on a vehicle with nylon fuel pipes.

Quick-Connect Fittings

Quick-connect fittings provide a simplified means of installing and connecting fuel system components. The fittings consist of a unique female connector and a compatible male pipe end. O-rings, located inside the female connector, provide the fuel seal. Integral locking tabs inside the female connector hold the fittings together.

Fuel Pipe O-Rings

O-rings seal the threaded connections in the fuel system. Fuel system O-ring seals are made of special material. Service the O-ring seals with the correct service part.

Scheme 21

The fuel rail assembly attaches to the engine intake manifold. The fuel rail assembly performs the following functions

1. Positions the injectors in the intake manifold
2. Distributes fuel evenly to the injectors

Fuel Injectors

The fuel injector assembly is a solenoid device controlled by the control module that meters pressurized fuel to a single engine cylinder. The control module energizes the high-impedance, 12 ohms, injector solenoid to open a normally closed ball valve. This allows fuel to flow into the top of the injector, past the ball valve, and through a director plate at the injector outlet. The director plate has machined holes that control the fuel flow, generating a spray of finely atomized fuel at the injector tip. Fuel from the injector tip is directed at the intake valve, causing the fuel to become further atomized and vaporized before entering the combustion chamber. This fine atomization improves fuel economy and emissions. The fuel pressure regulator compensates for engine load by increasing fuel pressure as the engine vacuum drops.

Fuel Metering Modes of Operation

The control module uses inputs from several sensors in order to determine how much fuel to supply to the engine. The fuel is delivered under one of several engine operating conditions called modes. The control module controls all modes.

Starting Mode

When the ignition is first turned ON, the control module energizes the fuel pump relay for 2 seconds. This allows the fuel pump to build pressure in the fuel system. The control module calculates the air/fuel ratio based on inputs from the engine coolant temperature (ECT), manifold absolute pressure (MAP), mass air flow (MAF), and throttle position (TP) sensors. The system stays in starting mode until the engine speed reaches a predetermined RPM.

Clear Flood Mode

If the engine floods, clear the engine by pressing the accelerator pedal down to the floor and then crank the engine. When the throttle position (TP) sensor is at wide open throttle (WOT), the control module reduces the fuel injector pulse width in order to increase the air to fuel ratio. The control module holds this injector rate as long as the throttle stays wide open and the engine speed is below a predetermined RPM. If the throttle is not held wide open, the control module returns to the starting mode.

Run Mode

The run mode has 2 conditions called Open Loop and Closed Loop. When the engine is first started and the engine speed is above a predetermined RPM, the system begins Open Loop operation. The control module ignores the signal from the heated oxygen sensor (HO2S). The control module calculates the air/fuel ratio based on inputs from the ECT, MAP, MAF, and TP sensors. The system stays in Open Loop until meeting the following conditions

1. The HO2S has varying voltage output, showing that the HO2S is hot enough to operate properly.
2. The ECT sensor is above a specified temperature.
3. A specific amount of time has elapsed after starting the engine.

Specific values for the above conditions exist for each different engine, and are stored in the electrically erasable programmable read-only memory (EEPROM). The system begins Closed Loop operation after reaching these values. In Closed Loop, the control module calculates the air/fuel ratio, injector ON time, based upon the signal from various sensors, but mainly from the HO2S. This allows the air/fuel ratio to stay very close to 14.7:1.

Acceleration Mode

When the driver pushes on the accelerator pedal, air flow into the cylinders increases rapidly. To prevent possible hesitation, the control module increases the pulse width to the injectors to provide extra fuel during acceleration. This is also known as power enrichment. The control module determines the amount of fuel required based upon the TP, the ECT, the MAP, the MAF, and the engine speed.

Deceleration Mode

When the driver releases the accelerator pedal, air flow into the engine is reduced. The control module monitors the corresponding changes in the TP, the MAF, and the MAP. The control module shuts OFF fuel completely if the deceleration is very rapid, or for long periods, such as long, closed-throttle coast-down. The fuel shuts OFF in order to prevent damage to the catalytic converters.

Battery Voltage Correction Mode

When the battery voltage is low, the control module compensates for the weak spark delivered by the ignition system in the following ways

1. Increasing the amount of fuel delivered
2. Increasing the idle RPM
3. Increasing the ignition dwell time

Fuel Cutoff Mode

The control module cuts off fuel from the fuel injectors when the following conditions are met in order to protect the powertrain from damage and improve driveability

1. The ignition is OFF. This prevents engine run-on.
2. The ignition is ON but there is no ignition reference signal. This prevents flooding or backfiring.
3. The engine speed is too high, above red line.
4. The vehicle speed is too high, above rated tire speed.
5. During an extended, high speed, closed throttle coast down. This reduces emissions and increases engine braking.
6. During extended deceleration, in order to protect the catalytic converters.

Fuel Trim

The control module controls the air/fuel metering system in order to provide the best possible combination of driveability, fuel economy, and emission control. The control module monitors the heated oxygen sensor (HO2S) signal voltage while in Closed Loop and regulates the fuel delivery by adjusting the pulse width of the injectors based on this signal. The ideal fuel trim values are around 0 percent for both short and long term fuel trim. A positive fuel trim value indicates the control module is adding fuel in order to compensate for a lean condition by increasing the pulse width. A negative fuel trim value indicates that the control module is reducing the amount of fuel in order to compensate for a rich condition by decreasing the pulse width. A change made to the fuel delivery changes the long and short term fuel trim values. The short term fuel trim values change rapidly in response to the HO2S signal voltage. These changes fine tune the engine fueling. The long term fuel trim makes coarse adjustments to fueling in order to re-center and restore control to short term fuel trim. A scan tool can be used to monitor the short and long term fuel trim values. The long term fuel trim diagnostic is based on an average of several of the long term speed load learn cells. The control module selects the cells based on the engine speed and engine load. If the control module detects an excessively lean or rich condition, the control module will set a fuel trim diagnostic trouble code (DTC).

Circuit Description

The Secondary Air Injection (AIR) System aids in the reduction of hydrocarbon exhaust emissions during a cold start-up. This occurs when the start-up engine coolant temperature (ECT) is between 5-50°C (41-122°F), and the intake air temperature (IAT) is between 5-60°C (41-140°F). The AIR pump operates 5-60 seconds after start-up.

The engine control module (ECM) activates the AIR system by simultaneously supplying a ground to the AIR pump and the AIR CNTRL relays. This action closes the relays' internal contacts. The AIR pump and the AIR check valve assembly are in turn energized, the pump runs and the check valve opens.

The AIR pump sends pressurized fresh air into the pipes/hoses through the check valve, and into the bank 2 exhaust manifold. The extra air accelerates the catalyst operation, helping it to reach operating temperature faster. The AIR pump remains ON for a short period of time after the check valve is commanded OFF. When the AIR pump is commanded OFF, it will not run or be activated until the next vehicle start. When the AIR system is inactive, the closed AIR check valve prevents air/exhaust flow in either direction.

The AIR system pressure sensor that integral to the check valve is used to monitor pressure at the AIR check valve assembly inlet, during the commanded ON/OFF states.

The control module supplies the internal pressure sensor with a 5-volt reference, an electrical ground and a signal circuit. The signal circuit provides the control module with a voltage relative to internal AIR pressure changes.

The AIR diagnostic uses 3 phases to test the AIR system

1. Phase 1-The ECM commands the AIR pump and check valve ON. The ECM monitors the AIR pressure sensor signal for an increase over BARO to a pre-determined threshold. This verifies a properly operating system.
2. Phase 2-The AIR pump remains commanded ON and the check valve is commanded OFF. The ECM monitors the AIR pressure sensor signal to increase further to pre-detremined threshold. This verifies that the check valve is not stuck open.
3. Phase 3-The AIR pump is commanded OFF. The ECM monitors the AIR pressure signal to return to BARO. This verifies the AIR pump is not stuck ON.

1. DTCs P0411 and P2430 run during Phase 1
2. DTCs P2430 and P2440 run during Phase 2
3. DTC P2444 runs during Phase 3

The AIR system includes the following components

1. The AIR pump-The electric AIR pump supplies pressurized, filtered air to the AIR check valve. The AIR pump is a turbine type pump that is permanently lubricated and requires no periodic maintenance.
2. The AIR solenoid-The AIR solenoids opens the AIR check valve when the solenoid is energized by the AIR CNTRL relay.
3. The AIR check valve assembly-The AIR solenoid valve/pressure sensor assembly has a solenoid mounted valve. When the valve is open by the solenoid, pressurized air from the AIR pump flows through the control solenoid valve/pressure sensor assembly and is directed into the bank 2 exhaust manifold through an outlet pipe.
4. The AIR pressure sensor-The AIR pressure sensor is a part of the AIR control solenoid valve/pressure sensor assembly. The sensor is a 3-wire sensor that measures the AIR system pressure at the AIR control solenoid valve/pressure sensor assembly inlet.
5. The AIR pump relay-The AIR pump relay supplies high current and battery voltage to the AIR pump. The ECM commands the relay ON by supplying a ground to the relay control circuit.
6. The AIR CNTRL relay-The AIR CNTRL relay supplies high current and battery voltage to the AIR solenoid. The ECM commands the relay ON by supplying a ground to the relay control circuit.
7. The pipes and hoses-The AIR system hose carries filtered air from the engine air cleaner to the AIR pump inlet. The pipe/hoses carry the air from the AIR pump to the AIR check valve assembly and on to the exhaust manifold.
8. The inlet filter-The AIR system does not have a separate inlet air filter. Filtered air is drawn from the engine air cleaner assembly.

Results of Incorrect Operation

The engine control module (ECM) monitors the Secondary air injection (AIR) System for faults during cold start-up operation. When the system's pressure or relay circuits operations vary too far from the predicted values, a DTC will set. Diagnostics detect the following conditions

1. A partially blocked or leaking AIR system
2. A malfunctioning AIR pump
3. A malfunctioning AIR control solenoid valve/pressure sensor assembly
4. A malfunctioning AIR pressure sensor
5. A restricted exhaust system, forward of the catalytic converter
6. A malfunctioning AIR pump and AIR valve relay

The following DTCs set when an AIR system fault is detected

1. DTC P0411-An AIR system insufficient airflow fault condition has been detected.
2. DTC P0412-An AIR valve relay coil circuit fault condition has been detected.
3. DTC P0418-An AIR pump relay coil circuit fault condition has been detected.
4. DTC P2430-An AIR pressure sensor stuck in range fault condition has been detected.
5. DTC P2431-An AIR pressure sensor range/performance fault condition has been detected.
6. DTC P2432-An AIR pressure sensor signal voltage below the minimum range of the sensor fault condition has been detected.
7. DTC P2433-An AIR pressure sensor signal voltage is above the maximum range of the sensor fault condition has been detected.
8. DTC P2440-An AIR check valve stuck open or airflow leak fault condition has been detected.
9. DTC P2444-An AIR pump stuck ON fault condition has been detected.

Scheme 22

The engine control module (ECM) is the control center for the throttle actuator control (TAC) system. The ECM determines the driver's intent based on input form the accelerator pedal position sensors, then calculates the appropriate throttle response based on the throttle position sensors. The ECM achieves throttle positioning by providing a pulse width modulated voltage to the throttle actuator motor. The throttle blade is spring loaded in both directions, and the default position is slightly open.

Normal Mode

During the operation of the TAC system, several modes, or functions, are considered normal. The following modes may be entered during normal operations

1. Minimum pedal value-At key-up, the ECM updates the learned minimum pedal value.
2. Minimum throttle position values-At key-up, the ECM updates the learned minimum throttle position value. In order to learn the minimum throttle position value, the throttle blade is moved to the Closed position.
3. Ice break mode-If the throttle blade is not able to reach a predetermined minimum throttle position, the ice break mode is entered. During the ice break mode, the ECM commands the maximum pulse width several times to the throttle actuator motor in the closing direction.
4. Minimum pedal value-At key-up, the ECM updates the learned minimum pedal value.
5. Battery saver mode-After a predetermined time without engine RPM, the ECM commands the battery saver mode. During the battery saver mode, the TAC module removes the voltage from the motor control circuits, which removes the current draw used to maintain the idle position and allows the throttle to return to the spring loaded default position.

Reduced Engine Power Mode

When the ECM detects a condition with the TAC system, the ECM may enter a reduced engine power mode. Reduced engine power may cause one or more of the following conditions

1. Acceleration limiting-The ECM will continue to use the accelerator pedal for throttle control, however, the vehicle acceleration is limited.
2. Limited throttle mode-The ECM will continue to use the accelerator pedal for throttle control, however, the maximum throttle opening is limited.
3. Throttle default mode-The ECM will turn OFF the throttle actuator motor, and the throttle will return to the spring loaded default position.
4. Forced idle mode-The ECM will perform the following actions: Limit engine speed to idle positioning the throttle position, or by controlling the fuel and spark if the throttle is turned OFF. Ignore the accelerator pedal input.
5. Engine shutdown mode-The ECM will disable fuel and de-energize the throttle actuator.

Illustration Tool Number/ Description CH-47976 Active Fuel Injector Tester (AFIT) CH-48027 Digital Pressure Gage CH-48096 EVAP Service Access Port Tool GE-41415-50 Fuel Fill Cap Adapter J-23738-A Mityvac J-26792 HEI Spark Tester J-34730-405 Injector Test Light J-35555 Metal Mityvac J-35616-200 Test Light - Probe Kit J-36850 Transjel Lubricant J-37088-A Fuel Line Disconnect Tool Set J-37287 Fuel Line Shut-Off Adapters J-38522 Variable Signal Generator J-39021 Fuel Injector Coil/Balance Tester J-41413-200 Evaporative Emissions System Tester (EEST) J-41413-SPT High Intensity White Light J-42960-2 Fuel Flapper Door Holder J-43244 Relay Puller Pliers J-44175 Fuel Composition Tester J-44602 Injector Test Adaptor J-45004 Fuel Drain Hose J-45722 Fuel Sender Lock Ring Wrench

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Scheme 29

Scheme 30

Scheme 31

Scheme 32

Scheme 33

Scheme 34

Scheme 35

Scheme 36

Scheme 37

Scheme 38

Scheme 39

Scheme 40

Scheme 41

Scheme 42

Scheme 43

See also:
• DTC P0016
• DTC P0340
• DTC P2430, P2431, P2432, or P2433
• Battery Negative Cable Disconnection and Connection
• Fastener Notice
• Control Module References
• Diagnostic Trouble Code (DTC) List - Vehicle
• Fuel Injector Sight Shield Replacement
• Cooling System Draining and Filling (Vac-N-Fill)
• Cooling System Draining and Filling (Static Fill)
• Heated Oxygen Sensor Resistance Learn Reset Notice
• Lifting and Jacking the Vehicle
• Oxygen Sensor Wiring Harness Heat Shield Replacement
• Front Air Deflector Replacement
• Instrument Panel Insulator Panel Replacement - Left Side
• Gasoline/Gasoline Vapors Caution
• Electrical Center Identification Views
• Rear Wheelhouse Panel Liner Replacement
• Rear Compartment Liner Replacement
• Engine Coolant Crossover Pipe Replacement
• Fuel and Evaporative Emission Pipe Caution
• Plastic Collar Quick Connect Fitting Service
• Fuel Pressure Relief (Without CH 48027)
• Ignition System Specifications
• Spark Plug Inspection
• Crankshaft Position System Variation Learn
• Exhaust Gas Recirculation (EGR) System Cleaning