Engine Controls - Removal & Installation Cadillac Escalade GMT800

AIR INDUCTION SYSTEMS

THROTTLE BODY

Removal (4.8L, 5.3L & 6.0L)

1. Disconnect negative battery cable. Drain cooling system into suitable container. Loosen retaining bolt on intake manifold sight shield at top of engine. (Scheme 1) Remove intake manifold sight shield from top of engine.
2. Loosen hose clamp at outlet side of MAF sensor. Loosen air inlet tube hose clamp at throttle body. Remove air inlet tube. Disconnect harness connectors at throttle body.
3. Reposition the coolant air bleed hose clamp at the throttle body. Remove the coolant air bleed hose from the throttle body. Remove throttle body mounting nuts. (Scheme 2) Remove throttle body. Remove throttle body flange gasket and discard.

Scheme 1

Scheme 2

1. Clean gasket surface on intake manifold and throttle body. Install NEW throttle body flange gasket. Install throttle body assembly. Install throttle body mounting nuts and tighten to specification. See «TORQUE SPECIFICATIONS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__torque-specifications) .
2. To complete installation, reverse removal procedure. Fill and bleed cooling system.
3. Connect a scan tool to Data Link Connector (DLC), under left side of instrument panel. Turn ignition on, with engine off. Using scan tool, ensure vehicle is not in a reduced engine power mode. Operate accelerator pedal while observing throttle angle on scan tool. Accelerator pedal should operate freely, without binding, between closed throttle and Wide Open Throttle (WOT).

Removal (8.1L)

Disconnect negative battery cable. Remove the intake air resonator. (Scheme 21) Disconnect the throttle actuator motor electrical connector. Remove the throttle body nuts. (Scheme 3) Remove the throttle body. Remove and discard the throttle body gasket.

Scheme 3

1. Clean gasket surface on intake manifold and throttle body. Install NEW throttle body flange gasket. Install throttle body assembly. Install throttle body mounting nuts and tighten to specification. See «TORQUE SPECIFICATIONS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__torque-specifications) . To complete installation, reverse removal procedure.
2. Connect a scan tool to Data Link Connector (DLC), under left side of instrument panel. Turn ignition on, with engine off. Using scan tool, ensure vehicle is not in a reduced engine power mode. Operate accelerator pedal while observing throttle angle on scan tool. Accelerator pedal should operate freely, without binding, between closed throttle and Wide Open Throttle (WOT).

COMPUTERIZED ENGINE CONTROLS

Note. All vehicles are equipped with a Powertrain Control Module (PCM) for engine control.

ELECTRICALLY ERASABLE PROGRAMMABLE READ-ONLY MEMORY

The Electrically Erasable Programmable Read-Only Memory (EEPROM) is a permanent memory that is part of PCM. EEPROM cannot be replaced. EEPROM contains program and calibration information that PCM uses to control powertrain. If PCM is replaced, ensure NEW PCM software/calibration is correct and is most recent version for vehicle. EEPROM must be programmed when NEW PCM is installed. Program EEPROM using latest software for that specific vehicle. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION.

POWERTRAIN CONTROL MODULE

Note. Before replacing PCM, carefully inspect all wiring and control components. Failure to test for short circuits may result in repeated PCM failure due to shorts and Quad-Driver failure. To prevent internal damage to PCM, ensure ignition switch is in OFF position when connecting or disconnecting PCM harness connectors or any electrical components. Inspect PCM connector gaskets and ensure they are installed correctly. PCM connector gaskets prevent contaminants from entering PCM.

1. Ensure ignition is off. Disconnect negative battery cable. Locate PCM at left front corner of engine compartment. (Scheme 4) Release PCM cover from mounting tabs on PCM bracket.
2. Remove PCM cover from PCM. Loosen PCM harness connector bolts. (Scheme 5) Disconnect PCM harness connectors. Release the PCM spring latch. Release PCM mounting tabs. Remove PCM.

Scheme 4

Scheme 5

1. Install PCM to bracket. Ensure PCM mounting tabs are engaged. Secure PCM spring latch. Connect harness connectors to PCM. Tighten PCM harness connector bolts to specification. See «TORQUE SPECIFICATIONS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__torque-specifications) .
2. Install PCM cover. Reconnect negative battery cable. If NEW PCM has been installed, PCM MUST be programmed. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION.

Throttle Actuator Control (TAC) module is located in rear of engine compartment, near underhood fuse block. (Scheme 6) Disconnect TAC module harness connectors. Remove TAC module nuts.

Install TAC module and TAC module nuts. Connect TAC module harness connectors.

Scheme 6

CKP SYSTEM VARIATION LEARN PROCEDURE

Note. The Crankshaft Position (CKP) system variation learn procedure is required when the following service procedures have been performed, regardless of whether DTC P0315 is set: CKP sensor replacement. Engine replacement. PCM replacement. Harmonic balancer replacement. Crankshaft replacement. Any engine repairs which disturb the CKP sensor relationship. For additional diagnostic information, see DTC P0315: CRANKSHAFT POSITION SENSOR VARIATION NOT LEARNED under DIAGNOSTIC TESTS in appropriate SELF-DIAGNOSTICS article.

1. Install a scan tool to Data Link Connector (DLC).
2. With a scan tool, monitor the powertrain control module for DTCs. If only DTC P0315 is set, go to next step. If a DTC other than P0315 is set, diagnose that DTC first. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in appropriate SELF-DIAGNOSTICS article.
3. With a scan tool, select the CRANKSHAFT POSITION VARIATION LEARN PROCEDURE.
4. The scan tool instructs you to perform the following: Set parking brake. Block drive wheels. DO NOT apply brake pedal. Observe fuel cut-off for applicable engine. Accelerate to Wide Open Throttle (WOT). Release throttle when fuel cut-off occurs. Engine should not accelerate beyond calibrated RPM value. Release throttle immediately if value is exceeded. Cycle ignition from OFF to ON. Apply and hold brake pedal. Start and idle engine. Turn A/C OFF. Vehicle must remain in Park or Neutral. The scan tool monitors certain component signals to determine if all the conditions are met to continue with the procedure. The scan tool only displays the condition that inhibits the procedure. The scan tool monitors the following components: Crankshaft Position (CKP) sensor activity. If there is a CKP sensor condition, refer to the applicable DTC that set. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in appropriate SELF-DIAGNOSTICS article. Camshaft Position (CMP) sensor activity. If there is a CMP sensor condition, refer to the applicable DTC that set. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in appropriate SELF-DIAGNOSTICS article. Engine Coolant Temperature (ECT). If the engine coolant temperature is not warm enough, idle the engine until the engine coolant temperature reaches the correct temperature.
5. With the scan tool, enable the crankshaft position system variation learn procedure.
6. Slowly increase the engine speed to the RPM that you observed.
7. Immediately release the throttle when fuel cut-off is reached.
8. The scan tool displays Learn Status: Learned this ignition. If the scan tool does NOT display this message and no additional DTCs set, see DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS under SELF-DIAGNOSTIC SYSTEM in appropriate SELF-DIAGNOSTICS article. If a DTC set, see DIAGNOSTIC TROUBLE CODE DEFINITIONS in appropriate SELF-DIAGNOSTICS article.
9. Turn OFF the ignition for 30 seconds after the learn procedure is completed successfully.

Note. Service of the PCM should normally consist of either replacement of the PCM or EEPROM programming. If the diagnostic procedures call for the PCM to be replaced, the PCM should be checked first to see if it is the correct part. If it is, remove the faulty PCM and install the new service PCM. The service PCM EEPROM will not be programmed. DTC P0601 and P0602 indicates the EEPROM is not programmed or has malfunctioned.

Note. Programing Powertrain Control Module requires a compatible scan tool and a Techline® terminal. Procedure uses a Tech 2 scan tool.

Remote Programming

Note. DO NOT program a control module unless you are directed by a service procedure or you are directed by a technical service bulletin. Programming a control module at any other time will not permanently correct a customer's concern.

1. Turn OFF the ignition.
2. Install the Tech 2® to the data link connector (DLC), with the Tech 2® turned OFF.
3. Turn ON Tech 2®. Press ENTER at title screen.
4. Turn ON the ignition, with the engine OFF.
5. Turn OFF all vehicle accessories.
6. Select SERVICE PROGRAMMING SYSTEM at the MAIN MENU.
7. Select REQUEST INFO.
8. Enter the vehicle description by following the on-screen instructions.
9. Verify that the correct VIN is entered on the Tech 2® and select YES.
10. Turn OFF the Tech 2®.
11. Disconnect the Tech 2® from the vehicle.
12. Turn OFF the ignition.
13. Connect the Tech 2® to the terminal.
14. Launch the TIS application at the terminal.
15. Select the SERVICE PROGRAMMING SYSTEM at the main screen.
16. Highlight the following information on the Select Diagnostic Tool and Programming Process Screen: Select DIAGNOSTIC TOOL, then select Tech 2. Select PROGRAMMING PROCESS. Identify whether an existing module is being reprogrammed or a module is being replaced with a new one. Select ECU LOCATION. Select vehicle.
17. Select NEXT.
18. Verify the connections and select NEXT.
19. Verify the VIN and select NEXT.
20. Select the appropriate controller for the vehicle being serviced.
21. Select the type of programming to be performed from the following categories: NORMAL - Used for updating an existing calibration or programming a new controller. VEHICLE CONFIGURATION INDEX (VCI) - Used for updating an existing controller or programming a new controller for newer vehicles whose VINs are not yet in the database. RECONFIGURE - Used to reconfigure a vehicle for changes in tire size and/or axle ratios.
22. Select NEXT.
23. Select the appropriate calibration file for the vehicle being serviced.
24. Select NEXT.
25. Verify your selection on the Summary screen.
26. Select NEXT.
27. Perform the CRANKSHAFT POSITION VARIATION RELEARN PROCEDURE using the SPECIAL FUNCTIONS feature, if applicable.
28. Close the application and return to the TIS APPLICATION SELECTION screen after the download is complete.
29. Turn OFF the Tech 2®.
30. Disconnect the Tech 2® from the terminal.
31. Connect the Tech 2® to the vehicle DLC, with the engine and the Tech 2® OFF.
32. Turn ON the Tech 2®.
33. Press ENTER at the TITLE screen.
34. Turn ON the ignition, with the engine OFF.
35. Select SERVICE PROGRAMMING SYSTEM.
36. Select the PROGRAM ECU function on the Tech 2.
37. Verify the VIN and calibration numbers, select CONTINUE.
38. Follow the on-screen instructions and select CONTINUE.
39. Select CONTINUE and exit the program after the Tech 2 displays PROGRAMMING WAS SUCCESSFUL.
40. Turn OFF the ignition.
41. Turn OFF the Tech 2.
42. Disconnect the Tech 2 from the vehicle.
43. Verify the control module programming was successful. Turn OFF the ignition for 30 seconds.
44. Start the engine. Repeat the Service Programming System procedure if the vehicle does not start or starts but runs rough.

Off-Board Remote Programming

Note. The Off-Board Programming Adapter Kit (J 41207-C) is required when a module must be programmed without having the vehicle present. The adapter allows the module to be turned ON and communicate with the scan tool.

1. Obtain the Vehicle Identification Number (VIN) of the vehicle for which the module is being programmed.
2. Launch the TIS application at the terminal.
3. Select the SERVICE PROGRAMMING SYSTEM.
4. Highlight the following information on the Select Diagnostic Tool and Programming Process Screen: Select DIAGNOSTIC TOOL, then select Tech 2. Select PROGRAMMING PROCESS. Identify whether an existing module is being reprogrammed or a module is being replaced with a new one. Select ECU LOCATION. Select OFF-BOARD PROGRAMMING ADAPTER.
5. Select NEXT.
6. Follow the directions on the Preparing for Communication screen for connecting the following components: The control module. The Off-Board Programming Adapter (OBPA). Refer to the TIS users guide for a listing of the OBPA. The Tech 2.
7. Select the SERVICE PROGRAMMING REQUEST INFORMATION function on the Tech 2.
8. Follow the Tech 2 instructions to obtain the module data and security information.
9. After the Tech 2 has received the data from the module, exit the Request Info mode.
10. Disconnect the Tech 2 from the OBPA.
11. Turn OFF the Tech 2.
12. Connect the Tech 2 to the terminal.
13. Turn ON the Tech 2.
14. Select NEXT at the terminal after the Tech 2 start-up screen appears.
15. Enter the VIN of the vehicle that will be receiving the control module.
16. Select NEXT.
17. Select the type of programming to be performed from the following categories: NORMAL - Used for updating an existing calibration or programming a new controller. VEHICLE CONFIGURATION INDEX (VCI) - Used for updating an existing controller or programming a new controller for newer vehicles whose VINs are not yet in the database. RECONFIGURE - Used to reconfigure a vehicle for changes in tire size and/or axle ratios.
18. Select NEXT.
19. Select a calibration on the Calibration Selection screen, if necessary.
20. Ensure all the desired folder tabs have a green check mark.
21. Select NEXT.
22. Verify the current and the selected calibration of the control module on the Summary screen.
23. Select NEXT.
24. Select OK.
25. On model year 1996 and newer controllers, a Crankshaft Position (CKP) relearn procedure box may appear. Select OK.
26. Follow the on-screen instructions, if any, when the Program Controller/Programming Complete screen appears.
27. Select CLOSE.
28. Turn OFF the Tech 2.
29. Disconnect the Tech 2 from the terminal.
30. Connect the Tech 2 to the OBPA.
31. Turn ON the Tech 2.
32. Select Enter at the title screen.
33. Select the SERVICE PROGRAMMING SYSTEM at the Main Menu.
34. Select the PROGRAM ECU function.
35. Select CONTINUE.
36. Follow the on-screen instructions.
37. Select Continue.
38. Select EXIT when the programming is complete.
39. Turn OFF the OBPA.
40. Turn OFF the Tech 2.
41. Disconnect the OBPA from the Tech 2 and the control module.

Off-Board Pass-Thru Programming

Note. The Off-Board Programming Adapter Kit (J 41207-C) is required when a module must be programmed without having the vehicle present. The adapter allows the module to be turned ON and communicate with the scan tool.

1. Launch the TIS application at the terminal.
2. Select the SERVICE PROGRAMMING SYSTEM.
3. Highlight the following information on the Select Diagnostic Tool and Programming Process Screen: Select DIAGNOSTIC TOOL, then select PASS-THRU. Select PROGRAMMING PROCESS. Identify whether an existing module is being reprogrammed or a module is being replaced with a new one. Select ECU LOCATION. Select OFF-BOARD PROGRAMMING ADAPTER.
4. Select NEXT.
5. Complete all terminal-directed data at the Preparing for Communication/Determine Vehicle screen until NEXT is highlighted.
6. Select NEXT.
7. Follow the on-screen instructions for connecting the following components: The control module. The Off-Board Programming Adapter (OBPA). Refer to the TIS users guide for a listing of the OBPA. The Tech 2.
8. Select NEXT.
9. Pass-Thru displays the VIN stored in the control module. If a new control module is being programmed, enter the correct VIN of the vehicle.
10. Select NEXT.
11. Select the appropriate options if the Options screen appears.
12. Select NEXT.
13. Select the type of programming to be performed from the following categories: NORMAL - Used for updating an existing calibration or programming a new controller. VEHICLE CONFIGURATION INDEX (VCI) - Used for updating an existing controller or programming a new controller for newer vehicles whose VINs are not yet in the database. RECONFIGURE - Used to reconfigure a vehicle for changes in tire size and/or axle ratios.
14. Select NEXT.
15. Select a calibration on the Calibration Selection screen, if necessary.
16. Ensure all the desired folder tabs have a green check mark.
17. Select NEXT.
18. Verify the current and the selected calibration of the control module on the Summary screen.
19. Select NEXT.
20. Select OK.
21. On model year 1996 and newer controllers, a Crankshaft Position (CKP) relearn procedure box may appear. Select OK.
22. Follow the on-screen instructions, if any, when the Program Controller/Programming Complete screen appears.
23. Select CLOSE.
24. Turn OFF the OBPA.
25. Turn OFF the Tech 2.
26. Disconnect the OBPA from the Tech 2 and the control module.

Pass-Thru Programming

Note. Pass-Thru programming allows the scan tool to remain connected to the terminal and to the vehicle throughout the programming process. The vehicle must be in close proximity to the terminal while using Pass-Thru.

1. Launch the TIS application at the terminal.
2. Select the SERVICE PROGRAMMING SYSTEM.
3. Highlight the following information on the Select Diagnostic Tool and Programming Process Screen: Select DIAGNOSTIC TOOL, then select PASS-THRU. Select PROGRAMMING PROCESS. Identify whether an existing module is being reprogrammed or a module is being replaced with a new one. Select ECU LOCATION. Select VEHICLE.
4. Select NEXT.
5. Complete all terminal-directed data on the Preparing for Communication/Determine Vehicle screen until NEXT is highlighted.
6. Select NEXT.
7. Follow the instructions on the Preparing for Communication screen.
8. Select NEXT.
9. Verify the VIN on the VALIDATE VEHICLE IDENTIFICATION NUMBER screen.
10. Select NEXT.
11. If an option screen appears, verify the vehicle configuration and/or RPO information.
12. Select NEXT.
13. Highlight the appropriate control module and programming type on the SUPPORTED CONTROLLERS screen.
14. Select NEXT.
15. Select the proper calibrations on the CALIBRATION SELECTION screen.
16. Ensure all the folder tabs have a green check mark.
17. Select NEXT.
18. Verify the current calibrations with the selected calibrations.
19. Select NEXT.
20. The TRANSFER DATA screen will appear until the progress bar reaches 100 percent. This may take up to 30 minutes.
21. Complete all of the terminal-directed data on the PROGRAMMING COMPLETE screen.
22. Turn OFF the Tech 2.
23. Disconnect the Tech 2® from the vehicle.

ACCELERATOR PEDAL POSITION SENSOR

Note. Handle the electronic throttle control components carefully. Use cleanliness in order to prevent damage. DO NOT drop the electronic throttle control components. DO NOT roughly handle the electronic throttle control components. DO NOT immerse the electronic throttle control components in cleaning solvents of any type.

Turn ignition off. Remove hush panel under left side of instrument panel. Disconnect Accelerator Pedal Position (APP) sensor harness connector. APP sensor is located behind accelerator pedal. (Scheme 7) Reposition carpet as necessary to access lower APP sensor retaining bolt. Remove 2 APP sensor retaining bolts. Remove APP sensor.

Install APP sensor. Tighten 2 APP sensor retaining bolts to specification. See TORQUE SPECIFICATIONS . To complete installation, reverse removal procedure.

Scheme 7

Removal & Installation (4.8L, 5.3L & 6.0L)

1. Clean area around Camshaft Position (CMP) sensor before removal to prevent debris from entering engine. CMP sensor is located at the top center rear of engine. (Scheme 8)
2. Disconnect CMP sensor harness connector. Remove CMP sensor retaining bolt. (Scheme 9) Remove CMP sensor. To install, reverse removal procedure. Tighten CMP sensor retaining bolt to specification. See «TORQUE SPECIFICATIONS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__torque-specifications).

Scheme 8

Scheme 9

Removal & Installation (8.1L)

1. Raise and support vehicle. Remove engine shield bolts and engine shield (if equipped). Disconnect CMP sensor harness connector. (Scheme 10)
2. Remove CMP sensor retaining bolt. Remove CMP sensor. If CMP sensor is not being replaced, inspect CMP sensor for wear, cracks or leakage. Inspect CMP sensor "O" ring for wear or damage. Replace as necessary.
3. Lubricate CMP sensor "O" ring with clean engine oil. To install, reverse removal procedure. Tighten CMP sensor retaining bolt to specification. See «TORQUE SPECIFICATIONS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__torque-specifications).

Scheme 10

Note. Crankshaft Position (CKP) sensor variation learn procedure will need to be performed whenever CKP sensor is removed or replaced.

1. Disconnect negative battery cable. Raise and support vehicle. Remove flywheel cover bolt. (Scheme 11) Remove starter mounting bolts. Disconnect oil level sensor harness connector. Slide starter forward until starter clears transmission. Disconnect electrical connectors from starter solenoid. Remove starter.
2. Clean area around Crankshaft Position (CKP) sensor before removal to prevent debris from entering engine. Disconnect CKP sensor harness connector. Remove CKP sensor retaining bolt and CKP sensor.
3. To install, reverse removal procedure. Tighten fasteners to specification. See «TORQUE SPECIFICATIONS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__torque-specifications). Perform «CKP SYSTEM VARIATION LEARN PROCEDURE»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__ckp-system-variation-learn-procedure) under PROGRAMMING.

Scheme 11

Scheme 12

1. Raise and support vehicle. Remove fuel line bracket retaining nut, attached to top left bellhousing stud. Remove fuel line bracket from bellhousing stud.
2. Disconnect CKP sensor harness connector. Spray penetrating oil around CKP sensor and allow it to soak in before attempting removal from engine block. Remove CKP sensor retaining bolt. Twist CKP sensor back and forth several times prior to removal from engine block. Remove CKP sensor.
3. Inspect CKP sensor for wear. CKP sensor is designed to contact reluctor wheel of crankshaft. Wear toward outside edges of CKP sensor tip is normal. Wear should not be visible toward center of CKP sensor tip. Replace CKP sensor as necessary. Inspect CKP sensor "O" ring for wear or damage. Replace as necessary. Lubricate CKP sensor "O" ring with clean engine oil.
4. Clean CKP sensor retaining bolt hole of any debris. Install CKP sensor into engine block. Ensure CKP sensor is fully seated against crankshaft reluctor ring. Upper flange on CKP sensor may not seat against engine block.
5. Apply Thread Adhesive (12345493) to CKP sensor retaining bolt threads. Install CKP sensor retaining bolt and tighten to specification. See «TORQUE SPECIFICATIONS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__torque-specifications) . To complete installation, reverse removal procedure. Perform «CKP SYSTEM VARIATION LEARN PROCEDURE»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__ckp-system-variation-learn-procedure) under PROGRAMMING.

Scheme 13

ENGINE COOLANT TEMPERATURE SENSOR

1. Turn ignition off. Disconnect negative battery cable. Drain coolant below level of Engine Coolant Temperature (ECT) sensor into a suitable container. Disconnect ECT sensor harness connector.
2. On 4.8L, 5.3L and 6.0L models, ECT sensor is located on left side of engine, near front of exhaust manifold. (Scheme 14)
3. On 8.1L models, ECT sensor is located on right side of engine, near middle of cylinder head. (Scheme 15) On all models, remove ECT sensor.

Scheme 14

Scheme 15

1. Whenever ECT sensor is removed, coat threads with Sealer (12346004) before reinstallation. Install ECT sensor into engine and tighten to specification. See «TORQUE SPECIFICATIONS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__torque-specifications) .
2. Reconnect harness connector to ECT sensor. Reconnect negative battery cable. Fill and bleed cooling system.

FUEL COMPOSITION SENSOR

Note. Fuel composition sensor is only used on models equipped with a flex-fuel 5.3L (RPO code L59).

Removal & Installation (5.3L)

1. Release fuel pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__fuel-system-pressure-release) under FUEL SYSTEMS. Raise and support vehicle. If equipped, remove the transfer case shield. Remove 2 fuel composition sensor bracket-to-frame rail mounting nuts. (Scheme 16)
2. Disconnect fuel composition sensor inlet and outlet pipes. See «FUEL LINE DISCONNECT FITTINGS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__fuel-line-disconnect-fittings) under FUEL SYSTEMS. Disconnect fuel composition sensor harness connector. Remove 2 fuel composition sensor bracket-to-frame rail mounting nuts.
3. Remove fuel composition sensor and mounting bracket from frame rail. Remove fuel composition sensor-to-mounting bracket bolts. Separate fuel composition sensor from mounting bracket. To install, reverse removal procedure. Tighten fasteners to specification. See «TORQUE SPECIFICATIONS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__torque-specifications).
4. Connect negative battery cable. Turn ignition switch to ON position for 2 seconds. Turn ignition switch to OFF position for 10 seconds. Turn ignition switch to ON position. Check for fuel leaks. Repair as necessary.

Scheme 16

Remove fuel tank. See FUEL TANK. Carefully remove fuel tank pressure sensor from fuel sending unit at top of fuel tank. (Scheme 17) To install, reverse removal procedure. Tighten fasteners to specification. See TORQUE SPECIFICATIONS. Check for fuel leaks.

Scheme 17

Intake Air Temperature (IAT) sensor is integral with Mass Airflow (MAF) sensor. See MASS AIRFLOW SENSOR .

Remove the intake manifold. See appropriate article in ENGINES. Gently pry up the knock sensor rubber covers. (Scheme 18) Disconnect knock sensor harness connector(s). Remove knock sensors. (Scheme 19) To install, reverse removal procedure. Tighten fasteners to specification. See TORQUE SPECIFICATIONS.

Scheme 18

Scheme 19

Raise and support vehicle. Drain cooling system. Disconnect knock sensor harness connector(s). (Scheme 10)and (Scheme 20). Remove knock sensor(s). To install, reverse removal procedure. Tighten knock sensor(s) to specification. See TORQUE SPECIFICATIONS. Fill and bleed cooling system.

Scheme 20

1. Loosen retaining bolt on intake manifold sight shield at top of engine. (Scheme 1) Remove intake manifold sight shield from top of engine. Remove intake manifold sight shield retainer bolts. Unclip accelerator cable from intake manifold sight shield retainer. Remove intake manifold sight shield retainer.
2. Disconnect Manifold Absolute Pressure (MAP) sensor harness connector. (Scheme 14) Remove MAP sensor from intake manifold. To install, coat MAP sensor seal with clean engine oil. Replace MAP sensor seal as necessary.
3. To complete installation, reverse removal procedure. Tighten fasteners to specification. See «TORQUE SPECIFICATIONS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__torque-specifications).

1. Loosen bolt on intake manifold sight shield at top of engine. Remove intake manifold sight shield from top of engine. Disconnect Manifold Absolute Pressure (MAP) sensor harness connector. (Scheme 15)
2. Remove MAP sensor retaining bolt and washer. Remove MAP sensor from intake manifold. To install, coat MAP sensor seal with Rubber Lubricant (9985770). DO NOT dip MAP sensor directly into Rubber Lubricant as vacuum port may become blocked. Replace MAP sensor seal as necessary.
3. To complete installation, reverse removal procedure. Tighten fasteners to specification. See «TORQUE SPECIFICATIONS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__torque-specifications).

MASS AIRFLOW SENSOR

1. Loosen hose clamps on both ends of air inlet tube. (Scheme 21) Remove upper radiator hose clip from air inlet tube. Remove air inlet tube.
2. Disconnect MAF sensor harness connector. Loosen MAF sensor-to-air cleaner hose clamp. Pull MAF sensor from air cleaner assembly.

To install, reverse removal procedure. Ensure arrow on MAF sensor is pointing away from air cleaner. Tighten MAF sensor hose clamps and air inlet tube hose clamp to specification. See TORQUE SPECIFICATIONS .

Scheme 21

OXYGEN SENSORS

Note. On 8.1L models, it may be necessary to lower the exhaust system to gain sufficient access to a HO2S and/or HO2S harness connector. Front Heated Oxygen Sensors (HO2S1, bank 1 and HO2S2, bank 1) are located in the exhaust pipes, below the respective exhaust manifold. (Scheme 22) Rear Heated Oxygen Sensors (HO2S1, bank 2 and HO2S2, bank 2) are mounted in the exhaust pipes, behind the respective catalytic converter. Oxygen sensors are equipped with a permanent pigtail which must remain intact when removing sensor.

1. Turn ignition off. Raise and support vehicle. Ensure oxygen sensor is free of contaminants. DO NOT use cleaning solvents of any type. Oxygen sensor may be difficult to remove when engine temperature is less than 120°F (48°C). Excessive removal force may damage threads in exhaust pipe.
2. Disconnect harness connector from appropriate HO2S. Carefully remove HO2S from exhaust pipe using Oxygen Sensor Tool (J-39194-B).

1. Whenever oxygen sensor is removed, coat threads with anti-seize compound (5613695) before reinstallation. New oxygen sensors already have this compound applied to threads.
2. Install oxygen sensor into exhaust pipe using Oxygen Sensor Tool (J-39194-B). Tighten oxygen sensor to specification. See «TORQUE SPECIFICATIONS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__torque-specifications) . Reconnect harness connector to oxygen sensor. Lower vehicle. Test system.

Scheme 22

THROTTLE POSITION SENSOR

Throttle Position (TP) sensor is not serviceable separately. Throttle body and TP sensor must be serviced as a complete assembly. See THROTTLE BODY under AIR INDUCTION SYSTEMS.

1. Loosen retaining bolt on intake manifold sight shield at top of engine. (Scheme 1) Remove intake manifold sight shield from top of engine.
2. Push retaining tab inward while pulling up on EVAP canister purge solenoid pipe connection to disconnect EVAP canister purge solenoid pipe from EVAP canister purge solenoid. (Scheme 23) EVAP canister purge solenoid is located near top right front of engine. (Scheme 14)
3. Disconnect EVAP canister purge solenoid harness connector. Remove EVAP canister purge solenoid retaining bolt. (Scheme 24) Remove EVAP canister purge solenoid and isolator from intake manifold.

Scheme 23

Scheme 24

To install, reverse removal procedure. Tighten EVAP canister purge solenoid retaining bolt to specification. See TORQUE SPECIFICATIONS .

1. Loosen bolt on intake manifold sight shield at top of engine. Remove intake manifold sight shield from top of engine. Disconnect EVAP canister purge solenoid harness connector. (Scheme 25)
2. Slide retaining tab on EVAP purge pipe connection to release position and disconnect EVAP purge pipe from EVAP canister purge solenoid. (Scheme 26) Remove EVAP canister purge solenoid retaining bolt. Remove EVAP canister purge solenoid.

Scheme 25

Scheme 26

To install, reverse removal procedure. Tighten EVAP canister purge solenoid retaining bolt to specification. See TORQUE SPECIFICATIONS .

Raise and support vehicle. EVAP canister vent valve is located on frame crossmember under vehicle. Disconnect EVAP canister vent pipe from EVAP canister vent valve. Disconnect EVAP canister vent valve harness connector. Detach EVAP canister vent valve from bracket. To install, reverse removal procedure.

FUEL SYSTEM PRESSURE RELEASE

Loosen retaining bolt on intake manifold sight shield at top of engine. Remove intake manifold sight shield from top of engine. Disconnect negative battery cable. Loosen fuel filler cap. Install Fuel Pressure Gauge (J-34730-1A) on fuel pressure connector of fuel rail. Wrap a shop towel around pressure connection when installing fuel pressure gauge to absorb fuel leakage. Place gauge bleed hose in container. Open bleed valve to release fuel pressure.

FUEL LINE DISCONNECT FITTINGS

Note. Fuel line disconnect fittings may contain metal or plastic collar. (Scheme 27)and (Scheme 28). Determine type of disconnect fitting used and use proper procedure for type of disconnect fitting being serviced.

Removal & Installation (Metal Collar)

1. Release fuel pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__fuel-system-pressure-release). Remove the retainer from the disconnect fitting.
2. Blow any dirt out of the disconnect fitting using compressed air. Choose correct size fitting tool from Disconnect Fitting Tool Set (J-37088-A). Insert disconnect fitting tool into female connector, then push inward to release the locking tabs. (Scheme 27) Pull connection apart.
3. Inspect all connections for dirt or burrs. If necessary, remove rust or burrs with an emery cloth. Using a clean shop towel, wipe off male tube ends. Clean or replace components and/or assemblies as necessary.
4. To install, ensure fuel line and disconnect fitting are clean. Lubricate fuel line and disconnect fitting with clean engine oil. Push both sides of disconnect fitting together to cause retaining tabs to snap into place. After connecting fitting, ensure connection is secure by pulling on both sides of disconnect fitting. Install retainer into the disconnect fitting.
5. Connect negative battery cable. Turn ignition switch to ON position for 2 seconds. Turn ignition switch to OFF position for 10 seconds. Turn ignition switch to ON position. Check for fuel leaks. Repair as necessary.

Scheme 27

Removal & Installation (Plastic Collar)

1. Release fuel pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__fuel-system-pressure-release). Blow any dirt out of the disconnect fitting using compressed air. Squeeze the 2 plastic retainer release tabs and pull the connection apart. (Scheme 28)
2. To install, ensure fuel line and disconnect fitting are clean. Lubricate fuel line and disconnect fitting with clean engine oil. Push both sides of disconnect fitting together to cause plastic retainer release tabs to snap into place. After connecting fitting, ensure connection is secure by pulling on both sides of disconnect fitting.
3. Connect negative battery cable. Turn ignition switch to ON position for 2 seconds. Turn ignition switch to OFF position for 10 seconds. Turn ignition switch to ON position. Check for fuel leaks. Repair as necessary.

Scheme 28

For removal and installation, see FUEL COMPOSITION SENSOR under SENSORS & SWITCHES.

1. Release fuel pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__fuel-system-pressure-release). Raise and support vehicle.
2. Before removal, clean fuel filter connections with a spray type engine cleaner, such as GM X-30A. DO NOT use any solvent that contains Methyl Ethyl Ketone (MEK). Solvents containing MEK may damage fuel system components.
3. Using a flare nut wrench and backup wrench, loosen the fuel lines from the fuel filter. (Scheme 29) Remove the fuel filter outlet line from the retainer and reposition the line out of the way.
4. Slide fuel filter from fuel filter bracket. Drain any remaining fuel into an approved container. Inspect fuel line "O" rings for cuts, nicks, swelling or distortion. Replace "O" rings as necessary.

Scheme 29

To install, reverse removal procedure. Tighten fuel line fittings to specification. See TORQUE SPECIFICATIONS . Turn ignition switch to ON position for 2 seconds. Turn ignition switch to OFF position for 10 seconds. Turn ignition switch to ON position. Check for fuel leaks. Repair as necessary.

Scheme 30

1. Disconnect negative battery cable. Loosen retaining bolt on intake manifold sight shield at top of engine. (Scheme 1) Remove intake manifold sight shield from top of engine. Remove intake manifold sight shield retainer bolts. Remove intake manifold sight shield retainer.
2. Release fuel pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__fuel-system-pressure-release). Before removal, clean area surrounding fuel pressure regulator with a spray type engine cleaner, such as GM X-30A. DO NOT use any solvent that contains Methyl Ethyl Ketone (MEK). Solvents containing MEK may damage fuel system components.
3. Disconnect the fuel pressure regulator vacuum line. Remove the fuel pressure regulator retainer. (Scheme 31) Remove the fuel pressure regulator. Ensure fuel pressure regulator filter, back-up ring and "O" rings are not still in the fuel rail.

Scheme 31

1. Install back-up ring, "O" ring, fuel pressure regulator filter and remaining "O" ring onto the fuel pressure regulator. Lubricate the fuel pressure regulator "O" rings with clean engine oil. Install the fuel pressure regulator.
2. Install NEW fuel pressure regulator retainer. Connect fuel pressure regulator vacuum line. To complete installation, reverse removal procedure.
3. Turn ignition switch to ON position for 2 seconds. Turn ignition switch to OFF position for 10 seconds. Turn ignition switch to ON position. Check for fuel leaks. Repair as necessary. Tighten intake manifold sight shield bolt and intake manifold sight shield retainer bolts to specification. See «TORQUE SPECIFICATIONS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__torque-specifications) .

1. Disconnect negative battery cable. Loosen retaining bolt on intake manifold sight shield at top of engine. Remove intake manifold sight shield from top of engine.
2. Release fuel pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__fuel-system-pressure-release). Before removal, clean area surrounding fuel pressure regulator with a spray type engine cleaner, such as GM X-30A. DO NOT use any solvent that contains Methyl Ethyl Ketone (MEK). Solvents containing MEK may damage fuel system components.
3. Disconnect the fuel pressure regulator vacuum line. Remove the fuel pressure regulator retainer. (Scheme 32) Remove the fuel pressure regulator. Ensure small "O" ring, fuel pressure regulator filter, large "O" ring and back-up ring are not still in the fuel rail.

Scheme 32

1. Install back-up ring onto fuel pressure regulator, followed by the large "O" ring, fuel pressure regulator filter and small "O" ring. (Scheme 32) Lubricate large and small fuel pressure regulator "O" rings with clean engine oil.
2. Push fuel pressure regulator into fuel pressure regulator housing on fuel rail. Install a NEW fuel pressure regulator retainer. Connect fuel pressure regulator vacuum line. To complete installation, reverse removal procedure.
3. Turn ignition switch to ON position for 2 seconds. Turn ignition switch to OFF position for 10 seconds. Turn ignition switch to ON position. Check for fuel leaks. Repair as necessary. Tighten intake manifold sight shield retaining bolt to specification. See «TORQUE SPECIFICATIONS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__torque-specifications).

Note. DO NOT handle the fuel sending unit assembly by the fuel pipes. The amount of leverage generated by handling the fuel sending unit assembly by the fuel pipes could damage the joints.

1. Fuel pump is located in fuel tank and is integral with fuel sending unit assembly. Remove fuel tank. See «FUEL TANK»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation). Using compressed air, clean area at top of fuel tank around fuel sending unit. (Scheme 33)
2. Disconnect fuel lines from fuel tank sending unit. See «FUEL LINE DISCONNECT FITTINGS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__fuel-line-disconnect-fittings).
3. Remove fuel sending unit assembly retaining ring using Retaining Ring Remover/Installer (J-44402). Lift fuel sending unit assembly from fuel tank. Drain any remaining fuel from the fuel sending unit into an approved container. Remove and discard fuel sending unit "O" ring.

Scheme 33

Note. Fuel pump strainer must be in a horizontal position when installing fuel tank sending unit into fuel tank. Ensure fuel pump strainer does not block the travel of the fuel sensing unit float arm.

Clean fuel sending unit sealing area. Install NEW fuel sending unit "O" ring onto the fuel tank opening. Lower fuel tank sending unit into fuel tank. Install fuel sending unit assembly retaining ring using Retaining Ring Remover/Installer (J-44402). Reinstall fuel tank. See FUEL TANK . Check for fuel leaks.

Note. An 8-digit part identification number can be found on the fuel rail assembly. Refer to this number if service or part replacement is necessary.

1. Disconnect negative battery cable. Loosen retaining bolt on intake manifold sight shield at top of engine. (Scheme 1) Remove intake manifold sight shield from top of engine. Remove intake manifold sight shield retainer bolts. Unclip accelerator cable from intake manifold sight shield retainer. Remove intake manifold sight shield retainer.
2. Release fuel pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__fuel-system-pressure-release). Before removal, clean fuel rail assembly with a spray type engine cleaner, such as GM X-30A. DO NOT use any solvent that contains Methyl Ethyl Ketone (MEK). Solvents containing MEK may damage fuel system components.
3. Remove upper engine wiring harness retainer nut. Disconnect EVAP purge solenoid harness connector. Disconnect harness connectors from generator, knock sensor and Manifold Absolute Pressure (MAP) sensor.
4. Remove the knock sensor harness connector from the intake manifold. Disconnect the electrical connectors from ignition coils on both sides. Remove the harness clips from the fuel rail. Reposition upper engine wiring harness aside.
5. Label injector harness connectors for installation reference. Pull Connector Position Assurance (CPA) on injector harness connector upward. (Scheme 34) While pushing injector harness connector tab inward, release CPA. Disconnect injector harness connector. Disconnect remaining injector harness connectors in same manner.
6. Remove the positive crankcase ventilation hose. Disconnect fuel feed and return lines at fuel rail. See «FUEL LINE DISCONNECT FITTINGS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__fuel-line-disconnect-fittings). Disconnect fuel pressure regulator vacuum line. On models equipped with gasoline-only 5.3L (RPO code LM7), loosen crossover pipe-to-right fuel rail retainer screw. (Scheme 31)
7. On all models, remove fuel rail retaining bolts. Remove fuel rail from intake manifold. Remove fuel injector retainer(s) and remove fuel injector(s) from fuel rail. Remove injector "O" rings and discard.

Scheme 34

1. On models equipped with gasoline-only 5.3L (RPO code LM7), coat NEW crossover pipe "O" ring with clean engine oil. Loosely install crossover pipe to right fuel rail. On all models, coat NEW upper injector "O" rings with clean engine oil. Install injector(s) into fuel rail. Install injector retainer(s). Ensure injector(s) rotate smoothly and freely. If "O" rings are installed incorrectly, injectors will bind.
2. Coat NEW lower injector "O" rings with clean engine oil. Install fuel rail. Apply a small amount of Threadlock (12345382) to threads on fuel rail retaining bolts. Install fuel rail retaining bolts and tighten to specification. See «TORQUE SPECIFICATIONS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__torque-specifications) . Tighten crossover pipe-to-right fuel rail retainer screw. Rotate injectors as necessary in order to avoid stretching of injector harness.
3. To complete installation, reverse removal procedure. Turn ignition switch to ON position for 2 seconds. Turn ignition switch to OFF position for 10 seconds. Turn ignition switch to ON position. Check for fuel leaks. Repair as necessary.

Note. An 8-digit part identification number can be found on the fuel rail assembly. Refer to this number if service or part replacement is necessary.

1. Disconnect negative battery cable. Loosen retaining bolt on intake manifold sight shield at top of engine. Remove intake manifold sight shield from top of engine. Remove intake manifold sight shield bracket nuts and bracket.
2. Release fuel pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__fuel-system-pressure-release). Before removal, clean fuel rail assembly with a spray type engine cleaner, such as GM X-30A. DO NOT use any solvent that contains Methyl Ethyl Ketone (MEK). Solvents containing MEK may damage fuel system components.
3. Disconnect harness connectors from EVAP purge solenoid, generator and Electronic Throttle Control (ETC). Remove engine wiring harness bolt studs. Position upper engine wiring harness aside.
4. Label injector harness connectors for installation reference. Pull fuel injector harness connector top upward, but not past the White portion of the connector. (Scheme 35) Push fuel injector harness connector release tab inward, to release connector from fuel injector. Disconnect remaining injector harness connectors in same manner.
5. Disconnect the fuel feed and return lines from the fuel rail. Disconnect fuel pressure regulator vacuum line. Remove the fuel rail attaching bolts and remove the fuel rail. Remove fuel injector retainer(s) and remove fuel injector(s) from fuel rail. (Scheme 32) Remove and discard fuel injector "O" rings.

Scheme 35

Note. When ordering new fuel injectors, ensure to order the correct injector(s) for the application being serviced.

1. Lubricate "O" ring seals on NEW fuel injector(s) with clean engine oil. Install fuel injector(s) into fuel rail with injector electrical connector facing outwards. Install fuel injector retainer(s).
2. Apply a small amount of Threadlock (12345382) to threads on fuel rail mounting bolts. Install fuel rail. Tighten fasteners to specification. See «TORQUE SPECIFICATIONS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__torque-specifications) . Rotate injectors as necessary in order to avoid stretching of injector harness.
3. To complete installation, reverse removal procedure. Turn ignition switch to ON position for 2 seconds. Turn ignition switch to OFF position for 10 seconds. Turn ignition switch to ON position. Check for fuel leaks. Repair as necessary.

Removal (Single Tank Models & Front Tank On Dual Tank Models)

1. Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__fuel-system-pressure-release). On models with dual tanks, drain as much fuel from front tank as possible through fuel filler opening using a hand-operated pump or equivalent.
2. On all models, raise and support vehicle. Remove EVAP canister. See «EVAP CANISTER»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation) under EMISSION SYSTEMS & SUB-SYSTEMS. Loosen fuel filler hose clamp. Disconnect fuel filler hose from fuel filler pipe. Disconnect EVAP vent pipe at fuel tank clip. Loosen vent hose clamp near fuel tank. Remove vent hose from fuel tank.
3. On single tank models, drain as much fuel as possible through fuel filler hose using a hand-operated pump or equivalent. Locate fuel feed and return line fittings at front edge of fuel tank. (Scheme 36) Disconnect fuel feed and return line fittings at front edge of fuel tank. See «FUEL LINE DISCONNECT FITTINGS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__fuel-line-disconnect-fittings). Cap fuel lines to prevent possible fuel system contamination.
4. On all models, support fuel tank. Remove fuel tank strap bolts. (Scheme 37) Remove fuel tank straps. Lower rear of fuel tank slightly. On Suburban, remove fuel sending unit cover.
5. On dual tank models, disconnect EVAP pipe and fuel feed and return lines at fuel sending unit. See «FUEL LINE DISCONNECT FITTINGS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__fuel-line-disconnect-fittings). Cap fuel lines to prevent possible fuel system contamination.
6. On all models, disconnect fuel sending unit and fuel pressure sensor harness connectors. Remove fuel tank.

Scheme 36

Scheme 37

1. Position and support fuel tank, raising front of fuel tank first. Reconnect fuel tank sending unit and fuel pressure sensor harness connectors.
2. On dual tank models, connect EVAP pipe and fuel feed and return lines at fuel sending unit. See «FUEL LINE DISCONNECT FITTINGS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__fuel-line-disconnect-fittings) . On Suburban, install fuel sending unit cover.
3. On all models, raise fuel tank and install fuel tank straps. Install fuel tank strap retaining bolts and tighten to specification. See «TORQUE SPECIFICATIONS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__torque-specifications) .
4. To complete installation, reverse removal procedure. Lower vehicle. Add fuel to fuel tank. Turn ignition switch to ON position for 2 seconds. Turn ignition switch to OFF position for 10 seconds. Turn ignition switch to ON position. Check for fuel leaks. Repair as necessary.

Removal (Rear Tank On Dual Tank Models)

1. Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__fuel-system-pressure-release). Drain as much fuel as possible through fuel filler opening using a hand-operated pump or equivalent. Lower and remove spare wheel/tire. Raise and support vehicle. Remove the rear exhaust insulator. Remove spare tire rear crossmember.
2. Loosen the fuel tank fill hose clamp at the front tank. Separate the fill hose from the front tank. Loosen the fuel tank fill pipe hose clamp at the rear tank. Separate the fill pipe hose from the rear tank. Loosen the vent hose clamp at the rear tank. Separate the vent hose from the rear tank. Support rear fuel tank. Remove rear fuel tank strap bolts. (Scheme 38) Remove rear fuel tank straps.
3. Open the retaining clip and remove the fill hose from the clip. Disconnect the EVAP pipes. See «FUEL LINE DISCONNECT FITTINGS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__fuel-line-disconnect-fittings). Disconnect the fuel pipe at the fuel sending unit. Cap fuel and EVAP lines to prevent possible fuel system contamination.
4. Partially lower the rear tank. Disconnect the fuel tank electrical connectors. Completely lower the fuel tank. Remove the tank from the jack. If necessary, remove the sending unit.

Scheme 38

1. If necessary, install the sending unit. Install the tank onto the jack. Raise the fuel tank until the electrical connection can me made. Connect the fuel tank electrical connectors. Remove the caps from the EVAP and fuel pipes. Connect the fuel pipe at the fuel sending unit. See «FUEL LINE DISCONNECT FITTINGS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__fuel-line-disconnect-fittings) . Connect the EVAP tubes.
2. Install the hose to the retaining clip. Close the retaining clip. Completely raise the fuel tank. Install the fuel tank straps. Install the fuel tank strap bolts. Tighten to specification. See «TORQUE SPECIFICATIONS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__torque-specifications) . Remove the jack from the fuel tank.
3. Install the vent hose to the rear tank. Tighten the vent hose clamp at the rear tank. Install the fill pipe hose to the rear tank. Tighten the fuel tank fill pipe hose clamp at the rear tank. Install the fill hose to the front tank. Tighten the fill hose clamp at the front tank. Install the spare tire hoist crossmember and bolts. Tighten to specification. See «TORQUE SPECIFICATIONS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__torque-specifications) .
4. Install the rear exhaust insulator. Lower the vehicle. Install the spare tire. Install the spare tire stowage lock cylinder. Refill the fuel tank. Install the fuel fill cap. Connect the negative battery cable. Turn ignition switch to ON position for 2 seconds. Turn ignition switch to OFF position for 10 seconds. Turn ignition switch to ON position. Check for fuel leaks. Repair as necessary.

FUEL TANK PRESSURE SENSOR

For removal and installation, see FUEL TANK PRESSURE SENSOR under SENSORS & SWITCHES.

See OXYGEN SENSORS under SENSORS & SWITCHES.

For removal and installation, see THROTTLE BODY under AIR INDUCTION SYSTEMS.

CAMSHAFT POSITION SENSOR

For removal and installation, see CAMSHAFT POSITION SENSOR under SENSORS & SWITCHES.

CRANKSHAFT POSITION SENSOR

For removal and installation, see CRANKSHAFT POSITION SENSOR under SENSORS & SWITCHES.

Note. Number in parenthesis refer to numbers in illustrations.

Note. There are 2 different manufacturers for the spark plug wire, ignition coils and coil brackets. They are as follows: The Melco® ignition coil is a square design (1). The Delphi® ignition coil is a round design (2). (Scheme 39)and (Scheme 40).

1. Turn ignition off. Disconnect negative battery cable. On 4.8L, 5.3L and 6.0L models, loosen retaining bolt on intake manifold sight shield at top of engine. (Scheme 1) Remove intake manifold sight shield from top of engine.
2. On all models, remove spark plug wire(s) from appropriate ignition coil(s). Disconnect harness connector(s) from appropriate ignition coil(s). Remove retaining bolts from appropriate ignition coil(s). Remove ignition coil(s) from engine.
3. To install, reverse removal procedure. Tighten fasteners to specification. See «TORQUE SPECIFICATIONS»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__torque-specifications).

Scheme 39

Scheme 40

KNOCK SENSORS

For removal and installation, see KNOCK SENSORS under SENSORS & SWITCHES.

Remove the spark plug wire. See SPARK PLUG WIRES . Loosen the spark plug 1 or 2 turns. Brush or using compressed air, blow away any dirt from around the spark plug. Remove the spark plug. If removing more than one plug, place each plug in a tray marked with the corresponding cylinder number.

Correctly position the spark plug washer. Inspect the spark plug gap. Adjust the gap as needed. Spark plug gap should be 0.060" (1.524 mm). Hand start the spark plug in the corresponding cylinder. Tighten the spark plug to specification. See TORQUE SPECIFICATIONS . Install the spark plug wire.

Note. Number in parenthesis refer to numbers in illustrations.

Note. There are 2 different manufacturers for the spark plug wire, ignition coils and coil brackets. They are as follows: The Melco® spark plug wire will have a blue foil mark on it, and the wire is 5.70" (145 mm) in length from cable seal to cable seal (1). The Delphi® spark plug wire will have a white foil mark on it, and the wire is 4.30" (110 mm) in length cable seal to cable seal (2). (Scheme 41)

To remove the spark plug wire from the ignition coil and the spark plug, twist the spark plug wire boot a 1/2 turn. Pull only on the boot in order to remove the wire from the spark plug. To install, reverse removal procedure.

Scheme 41

Removal (1500)

1. Raise and suitably support the vehicle. Disconnect the Evaporative Emission (EVAP) canister vent pipe from the canister. Remove the vent pipe clip from the canister bracket. Disconnect the EVAP pipe from the canister.
2. Disconnect the fuel tank vapor pipe from the canister. Cap the EVAP pipes in order to prevent possible EVAP system contamination. Remove the EVAP canister bolts. Remove the EVAP canister. (Scheme 42)

To install, reverse removal procedure. Tighten EVAP canister mounting bolts to specification. See TORQUE SPECIFICATIONS . Lower vehicle.

Scheme 42

Removal (2500)

1. Raise and suitably support the vehicle. Remove the drive shaft. Disconnect the Evaporative Emission (EVAP) canister vent pipe from the canister. Remove the vent pipe clip from the canister bracket. Remove the EVAP pipe clip from the canister bracket. Disconnect the EVAP canister pipe from the canister. Disconnect the EVAP canister pipe from the EVAP/fuel pipe assembly.
2. Facing toward the front of the vehicle, slide the EVAP canister to the left. (Scheme 43) Lift up and remove the EVAP canister. Cap the EVAP pipes in order to prevent possible EVAP system contamination. If necessary, remove the small EVAP pipe from the canister.

To install, reverse removal procedure. Tighten EVAP canister mounting bolts to specification. See TORQUE SPECIFICATIONS . Lower vehicle.

Scheme 43

EVAP CANISTER PURGE SOLENOID

For removal and installation, see EVAP CANISTER PURGE SOLENOID under SOLENOIDS.

EVAP CANISTER VENT VALVE

For removal and installation, see EVAP CANISTER VENT VALVE under SOLENOIDS.

Inspection Procedure

Note. DO NOT perform this procedure unless instructed by an Evaporative Emission (EVAP) diagnostic.

Note. Use EVAP Pressure/Purge Diagnostic Station (J-41413) in order to provide a clean, dry, low pressure gas source.

1. Turn ignition off. Remove EVAP canister purge solenoid. See «EVAP CANISTER PURGE SOLENOID»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation) . Lightly tap the EVAP canister purge solenoid on a clean, hard surface. Inspect for carbon particles exiting either of the vacuum ports. If no carbon particles are found, reinstall EVAP canister purge solenoid and perform «CLEANING PROCEDURE»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__cleaning-procedure) .
2. If carbon particles are found during the inspection procedure, replace EVAP canister purge solenoid and perform «CLEANING PROCEDURE»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__cleaning-procedure) . If you were instructed to replace the EVAP canister purge solenoid, and no carbon particles are found, return to the EVAP diagnostic procedure. DO NOT perform the «CLEANING PROCEDURE»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation__cleaning-procedure) .

Cleaning Procedure

1. Remove EVAP canister. See «EVAP CANISTER»(/cadillac/escalade/gmt800-2001-2006/remont/removal-installation/#engine-controls-removal-installation) . Turn main valve to OFF position on EVAP Pressure/Purge Diagnostic Station. Disconnect hose from EVAP Pressure/Purge Diagnostic Station pressure regulator. Using a section of vacuum hose, connect one end to EVAP Pressure/Purge Diagnostic Station pressure regulator. Connect other end of vacuum hose to EVAP canister side of purge pipe.
2. Turn main nitrogen cylinder valve to ON and continue to discharge nitrogen for 15 seconds. If the nitrogen does not dislodge the carbon particles, replace the purge pipe. Replace EVAP canister. Continue with DTC test.

TORQUE SPECIFICATIONS

TORQUE SPECIFICATIONS

See also:
• TORQUE SPECIFICATIONS
• CKP SYSTEM VARIATION LEARN PROCEDURE
• FUEL SYSTEM PRESSURE RELEASE
• FUEL LINE DISCONNECT FITTINGS
• FUEL TANK
• MASS AIRFLOW SENSOR
• FUEL COMPOSITION SENSOR
• FUEL TANK PRESSURE SENSOR
• OXYGEN SENSORS
• THROTTLE BODY
• CAMSHAFT POSITION SENSOR
• CRANKSHAFT POSITION SENSOR
• KNOCK SENSORS
• EVAP CANISTER PURGE SOLENOID
• EVAP CANISTER VENT VALVE
• CLEANING PROCEDURE