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Engine Controls/fuel - 3.6l - Repair Instructions Buick LaCrosse II

Testing & Diagnostics 46 illustrations ~7497 words

Crankshaft Position System Variation Learn

Note. The Crankshaft Position System Variation Learn procedure is also required when the following service procedures have been performed, regardless of whether DTC P0315 is set: An engine replacement A engine control module (ECM) or body control module (BCM) replacement A crankshaft balancer replacement A crankshaft removal and/or replacement A crankshaft position sensor disturbance/removal and/or replacement Any engine repairs which disturb the crankshaft to crankshaft position sensor relationship.

Note. The ECM monitors certain component signals to determine if all the conditions are met to continue with the crankshaft position System Variation Learn Procedure. The scan tool only displays the condition that inhibits the procedure. The scan tool displays the signals of the following components: Crankshaft position sensors activity-If there is a crankshaft position sensor condition, refer to the applicable DTC that set. Camshaft position sensor signal activity-If there is a camshaft position sensor signal condition, refer to the applicable DTC that set. 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.

  1. Ignition ON, observe the DTC information with a scan tool. Verify no other DTCs are set, except DTCs P0300-P0306, or P0315. If DTCs are set, except DTCs P0300-P0304, or P0315, refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-trouble-code-dtc-list) for further diagnosis.
  2. With a scan tool, select the Crankshaft Position System Variation Learn Procedure and perform the following: NOTE: Close the hood. NOTE: The engine must be at operating temperature. Block drive wheels. Set parking brake. DO NOT apply brake pedal. Turn the air conditioning (A/C) OFF. When directed, apply and hold brake pedal for the duration of the procedure. Ignition ON, engine running at operating temperature. The vehicle must remain in Park or Neutral. NOTE: 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. Accelerate to wide open throttle (WOT) and release as soon as the fuel cut-off occurs. Accelerate to wide open throttle (WOT) and release when the fuel cut-off occurs.
  3. The scan tool displays Learn in Progress.
  4. The scan tool displays Learn Successful.
  5. If not successful, review the reject reason's on the scan tool and repeat step's 1-3.
  6. Verify DTC P0315 ran and passed This Ignition Cycle. If DTC P0315 failed or did not run This Ignition Cycle, or another DTC is present, refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-trouble-code-dtc-list) for the applicable DTC that set.
  7. Once the Crankshaft Position Variation Learn procedure has successfully completed, and in order to store the crankshaft position variation values in the ECM, turn OFF the ignition and verify all vehicle systems are OFF. This may take up to 2 minutes.

Scheme 40

Scheme 40: Engine Control Module Replacement
Scheme 40: Engine Control Module Replacement
CalloutComponent Name
Preliminary Procedure Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection .
1Electronic Control Module WARNING: Refer to Safety Glasses Warning . CAUTION: Always turn the ignition off when installing or removing the ECM connectors in order to prevent damage to the components. CAUTION: 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. Procedure Disconnect the electrical connectors. Release the retaining tab. If replacing, program the ECM. Refer to Control Module References . NOTE: Before removing the engine control module (ECM), record the oil life percentage remaining. Use the scan tool to reset the Engine Oil Life remaining back to the original percentage recorded.
WARNING
Refer to Safety Glasses Warning .
CAUTION
Always turn the ignition off when installing or removing the ECM connectors in order to prevent damage to the components.
CAUTION
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.
NOTE
Before removing the engine control module (ECM), record the oil life percentage remaining. Use the scan tool to reset the Engine Oil Life remaining back to the original percentage recorded.

Engine Control Module Replacement

Description

The engine control module (ECM) learns the airflow through the throttle body 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 throttle body coking. Anytime the throttle body airflow rate changes, for example due to cleaning or replacing, the values must be relearned.

An engine 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

Reset Procedure

  1. DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0116, P0117, P0118, P0121, P0122, P0123, P0128, P0171, P0172, P0174, P0175, P0201-P0206, P0222, P0223, P0300-P0306, P0351-P0356, P0496, P0506, P0507, P0601-P0604, P0606, P062B, P062F, P0630, P0641, P0651, P0697, P06A3, P1101, P1516, P2101, P2119, P2122, P2123, P2127, P2128, P16F3, P2135, P2138, P2176, or P2610 are not set.
  2. Ignition ON, engine OFF.
  3. The vehicle speed sensor (VSS) is 0 km/h (0 mph).

Learn Procedure

  1. DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0116, P0117, P0118, P0121, P0122, P0123, P0128, P0171, P0172, P0174, P0175, P0201-P0206, P0222, P0223, P0300-P0306, P0351-P0356, P0496, P0506, P0507, P0601-P0604, P0606, P062B, P062F, P0630, P0641, P0651, P0697, P06A3, P1101, P1516, P2101, P2119, P2122, P2123, P2127, P2128, P16F3, P2135, P2138, P2176, or P2610 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 voltage is greater than 11 V.

Reset/Learn Procedure

Reset Procedure - Performed after the throttle body is cleaned or replaced

  1. Ignition ON, engine OFF, perform the Idle Learn Reset in Module Setup with a scan tool.
  2. Engine idling, monitor the Throttle Body Idle Airflow Compensation parameter. The Throttle Body Idle Airflow Compensation value should equal 0 % and the engine should be idling at a normal idle speed.
  3. Clear the DTCs and return to the diagnostic that referred you here.

Learn Procedure - Performed after the ECM is programmed or replaced

  1. Engine idling for 3 minutes.
  2. Monitor the Desired Idle Speed and the actual Engine Speed with a scan tool.
  3. The ECM will start to learn the new idle cells and Desired Idle Speed should start to decrease.
  4. Ignition OFF for 60 s.
  5. Engine idling for 3 minutes.
  6. After the 3 minute run time the engine speed should return to normal. NOTE: During the drive cycle monitor the DTC information with a scan tool to verify DTC P0506 and P0507 do not set. If DTC P0506 and P0507 set, clear the DTCs 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.
  7. After the drive cycle, the engine speed should return to normal. If the engine idle speed has not been learned, turn OFF the ignition for 60 s and repeat step 6.
  8. Once the engine speed has returned to normal, clear DTCs and return to the diagnostic that referred you here.

Scheme 41

Scheme 41: Engine Coolant Temperature Sensor Replacement (LFW Or LFX)
Scheme 41: Engine Coolant Temperature Sensor Replacement (LFW Or LFX)
CalloutComponent Name
Preliminary Procedure Partially drain the cooling system. Refer to Cooling System Draining and Filling (Static Fill) , Cooling System Draining and Filling (GE 47716) .
1Engine Coolant Temperature Sensor CAUTION: Refer to Fastener Caution . Procedure Reposition the sensor heat shield. Disconnect the ECT sensor harness connector. Tighten 20 N.m (35 lb in)
CAUTION
Refer to Fastener Caution .

Engine Coolant Temperature Sensor Replacement (LFW or LFX)

Scheme 42

Scheme 42: Mass Airflow Sensor with Intake Air Temperature Sensor Replacement (LFW or LFX)
Scheme 42: Mass Airflow Sensor with Intake Air Temperature Sensor Replacement (LFW or LFX)
CalloutComponent Name
1Bolt (Qty: 2) CAUTION: Refer to Fastener Caution .
2Mass Airflow Sensor Procedure Disconnect the mass airflow sensor harness connector.
CAUTION
Refer to Fastener Caution .

Mass Airflow Sensor with Intake Air Temperature Sensor Replacement (LFW or LFX)

Scheme 43

Scheme 43: Manifold Absolute Pressure Sensor Replacement (LFW or LFX)
Scheme 43: Manifold Absolute Pressure Sensor Replacement (LFW or LFX)
CalloutComponent Name
Preliminary Procedure Remove the intake manifold cover. Refer to Intake Manifold Cover Replacement .
1Bolt (Qty: 4) CAUTION: Refer to Fastener Caution . Tighten 10 N.m (89 lb in)
2Throttle Body Procedure Disconnect the throttle body harness connector. Install a NEW throttle body seal. Perform the throttle learn procedure. Refer to Throttle/Idle Learn .
CAUTION
Refer to Fastener Caution .

Manifold Absolute Pressure Sensor Replacement (LFW or LFX)

Scheme 44

Scheme 44: Heated Oxygen Sensor Replacement - Bank 1 Sensor 1 (LFW or LFX)
Scheme 44: Heated Oxygen Sensor Replacement - Bank 1 Sensor 1 (LFW or LFX)
CalloutComponent Name
Preliminary Procedures Remove the air cleaner outlet duct. Refer to Air Cleaner Outlet Duct Replacement (LFW or LFX) .
1Heated Oxygen Sensor CAUTION: Refer to Heated Oxygen and Oxygen Sensor Caution . CAUTION: Refer to Fastener Caution . Procedure Disconnect the heated oxygen sensor harness connector. If reinstalling the old sensor, coat the threads with anti-seize compound. Refer to Adhesives, Fluids, Lubricants, and Sealers . TIP: A special anti-seize compound is used in the HO2S threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn away, but the glass beads remain, making the sensor easier to remove. New, or service replacement sensors already have the compound applied to the threads. If the sensor is removed from an exhaust component and if for any reason the sensor is to be reinstalled, the threads must have anti-seize compound applied before reinstallation. Tighten 42 N.m (31 lb in)
CAUTION
Refer to Fastener Caution .

Heated Oxygen Sensor Replacement - Bank 1 Sensor 1 (LFW or LFX)

Scheme 45

Scheme 45: Heated Oxygen Sensor Replacement - Bank 1 Sensor 2 (LFW or LFX)
Scheme 45: Heated Oxygen Sensor Replacement - Bank 1 Sensor 2 (LFW or LFX)
CalloutComponent Name
Preliminary Procedure Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
1Heated Oxygen Sensor CAUTION: Refer to Heated Oxygen and Oxygen Sensor Caution . CAUTION: Refer to Fastener Caution . Procedure Disconnect the heated oxygen sensor harness connector. If reinstalling the old sensor, coat the threads with anti-seize compound. Refer to Adhesives, Fluids, Lubricants, and Sealers . TIP: A special anti-seize compound is used in the HO2S threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn away, but the glass beads remain, making the sensor easier to remove. New, or service replacement sensors already have the compound applied to the threads. If the sensor is removed from an exhaust component and if for any reason the sensor is to be reinstalled, the threads must have anti-seize compound applied before reinstallation. Tighten 42 N.m (31 lb in)
CAUTION
Refer to Fastener Caution .

Heated Oxygen Sensor Replacement - Bank 1 Sensor 2 (LFW or LFX)

Scheme 46

Scheme 46: Heated Oxygen Sensor Replacement - Bank 2 Sensor 1 (LFW or LFX)
Scheme 46: Heated Oxygen Sensor Replacement - Bank 2 Sensor 1 (LFW or LFX)
CalloutComponent Name
1Heated Oxygen Sensor CAUTION: Refer to Heated Oxygen and Oxygen Sensor Caution . CAUTION: Refer to Fastener Caution . Procedure Disconnect the heated oxygen sensor harness connector. If reinstalling the old sensor, coat the threads with anti-seize compound. Refer to Adhesives, Fluids, Lubricants, and Sealers . TIP: A special anti-seize compound is used in the HO2S threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn away, but the glass beads remain, making the sensor easier to remove. New, or service replacement sensors already have the compound applied to the threads. If the sensor is removed from an exhaust component and if for any reason the sensor is to be reinstalled, the threads must have anti-seize compound applied before reinstallation. Tighten 42 N.m (31 lb in)
CAUTION
Refer to Fastener Caution .

Heated Oxygen Sensor Replacement - Bank 2 Sensor 1 (LFW or LFX)

Scheme 47

Scheme 47: Heated Oxygen Sensor Replacement - Bank 2 Sensor 2 (LFW or LFX)
Scheme 47: Heated Oxygen Sensor Replacement - Bank 2 Sensor 2 (LFW or LFX)
CalloutComponent Name
Preliminary Procedure Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
1Heated Oxygen Sensor CAUTION: Refer to Heated Oxygen and Oxygen Sensor Caution . CAUTION: Refer to Fastener Caution . Procedure Disconnect the heated oxygen sensor harness connector. If reinstalling the old sensor, coat the threads with anti-seize compound. Refer to Adhesives, Fluids, Lubricants, and Sealers . TIP: A special anti-seize compound is used in the HO2S threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn away, but the glass beads remain, making the sensor easier to remove. New, or service replacement sensors already have the compound applied to the threads. If the sensor is removed from an exhaust component and if for any reason the sensor is to be reinstalled, the threads must have anti-seize compound applied before reinstallation. Tighten 42 N.m (31 lb in)
CAUTION
Refer to Fastener Caution .

Heated Oxygen Sensor Replacement - Bank 2 Sensor 2 (LFW or LFX)

Scheme 48

Scheme 48: Accelerator Pedal Position Sensor Replacement
Scheme 48: Accelerator Pedal Position Sensor Replacement
CalloutComponent Name
1Accelerator Pedal Position Sensor Bolt CAUTION: Refer to Fastener Caution Tighten 9 N.m(80 lb in)
2Accelerator Pedal Position Sensor
CAUTION
Refer to Fastener Caution

Accelerator Pedal Position Sensor Replacement

Throttle Body Assembly Replacement (LFW or LFX)

CalloutComponent Name
Preliminary Procedure Remove the intake manifold cover. Refer to Intake Manifold Cover Replacement .
1Bolt (Qty: 4) CAUTION: Refer to Fastener Caution . Tighten 10 N.m (89 lb in)
2Throttle Body Procedure Disconnect the throttle body harness connector. Install a NEW throttle body seal. Perform the throttle learn procedure. Refer to Throttle/Idle Learn .
CAUTION
Refer to Fastener Caution .

Throttle Body Assembly Replacement (LFW or LFX)

Throttle Body Inspection and Cleaning

Note. Over extended time and mileage, deposits may accumulate on the back of the throttle valve plate. The source of the deposit is exhaust gas recirculation (EGR) gas. Typically these deposits pose no problem. Occasionally the deposit may accumulate to a point where perceived pedal effort or throttle valve movement is effected. This procedure should not be performed on vehicles with mileage under 80 450 km (50, 000 mi).

  1. Remove the air cleaner outlet duct. Refer to «Air Cleaner Outlet Duct Replacement (LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  2. Inspect the throttle body bore and the throttle valve plate for deposits. You will need to open the throttle valve in order to inspect all surfaces.
  3. Clean the throttle body bore and the throttle valve plate using a clean shop towel with GM Top Engine Cleaner. Refer to «Adhesives, Fluids, Lubricants, and Sealers»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-specifications__adhesives-fluids-lubricants-and-sealers) .
  4. Install the air cleaner outlet duct. Refer to «Air Cleaner Outlet Duct Replacement (LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  5. Perform the Throttle/Idle Learn procedure. Refer to «Throttle/Idle Learn»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .

Fuel Pressure Relief

WARNINGFuel that flows out at high pressure can cause serious injury to the skin and eyes. ALWAYS depressurize the fuel system before removing components that are under high fuel pressure.
  1. Remove the fuel pump module 20A fuse from the underhood electrical center.
  2. Start the vehicle and allow the engine to idle until the engine stops. The engine will stop in approximately 20-30 seconds.
  3. Turn the ignition OFF.

Fuel Pressure Gauge Installation and Removal

Special Tools

CH 48027 Digital Pressure Gauge

For equivalent regional tools, refer to Special Tools (Diagnostic Tools)

Installation Procedure

WARNINGRemove the fuel tank cap and relieve the fuel system pressure before servicing the fuel system in order to reduce the risk of personal injury. After you relieve the fuel system pressure, a small amount of fuel may be released when servicing the fuel lines, the fuel injection pump, or the connections. In order to reduce the risk of personal injury, cover the fuel system components with a shop towel before disconnection. This will catch any fuel that may leak out. Place the towel in an approved container when the disconnection is complete.
  1. Relieve the fuel system pressure. Refer to «Fuel Pressure Relief»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions__fuel-pressure-relief) .
  2. Connect the CH 48027 gauge (1) to the CH 48027 adapter (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 gauge (1), refer to the manufacture's directions.

Removal Procedure

  1. Relieve the fuel system pressure, if required. Perform the following steps: Wrap a shop towel around the fuel rail service port. Place the hose on the CH 48027 adapter (2) into an approved gasoline container. Open the valve on the CH 48027 adapter (2) in order to bleed any fuel from the fuel rail. Close the valve on the CH 48027 adapter (2). Remove the hose on the CH 48027 adapter (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 gauge (1) from the CH 48027 gauge (2).
  3. Disconnect the CH 48027 adapter (2) from the CH 48027 adapter (3).
  4. Disconnect the CH 48027 adapter (3) 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.

Metal Collar Quick Connect Fitting Service

Special Tools

  1. CH-41769 Fuel Line Disconnect Tool Set
  2. CH-44581 Fuel Line Disconnect Tool

For equivalent regional tools, refer to Special Tools (Diagnostic Tools) .

  1. Relieve the fuel system pressure. Refer to «Fuel Pressure Relief»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions__fuel-pressure-relief) .
  2. Remove the retainer from the quick-connect fitting.
  3. Blow dirt out of the fitting using compressed air.
  4. Depending on the fuel line size and ability to access the fitting, choose the appropriate tool: CH-41769 fuel line disconnect tool set or CH-44581 fuel line disconnect tool. Insert the CH-41769 fuel line disconnect tool set or CH-44581 fuel line disconnect 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.
  8. 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 quick-connect fitting together to cause the retaining tabs to snap into place.
  3. Pull on both sides of the quick-connect fitting to make sure the connection is secure.
  4. Install the retainer to the quick-connect fitting.
  5. Inspect for leaks using the following procedure: Turn the ignition ON, with the engine OFF for 2 seconds. Turn the ignition OFF, for 10 seconds. Turn the ignition ON, with the engine OFF for 2 seconds. Turn the ignition OFF. Inspect for leaks.

Note. If servicing a fuel system, insure the fuel pressure has been relieved.

Scheme 49

Scheme 49
Scheme 49

Note. There are several types of plastic collar fuel and evaporative emission quick connect fittings used on this vehicle. Bartholomew (1) Q Release (2) Squeeze to Release (3) Sliding Retainer (4) Global Connect (5) TI Loc (6) Safe Lock (7) Plastic Connector (8) The following instructions apply to all of these types of plastic collar quick connect fittings except where indicated.

  1. Using compressed air, blow any dirt out of the quick-connect fitting.
  2. This step applies to Bartholomew style connectors ONLY. Squeeze the plastic quick-connect fitting release tabs.
  3. This step applies to Q Release style connectors ONLY. Release the fitting by Pushing the tab toward the other side of the slot in the fitting.
  4. This step applies to Squeeze to Release style connectors ONLY. Squeeze where indicated by arrows on both sides of the plastic ring surrounding the quick-connect fitting.
  5. This step applies to Squeeze to Release style connectors ONLY. Push in the male side slightly in order to slide the retainer away from the retainers, squeeze where indicated by arrows on both sides of the plastic ring surrounding the quick-connect fitting.
  6. This step applies to 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 doesn't move try pressing the tab in from the opposite side. The tab will only move in one direction.
  7. This step applies to the Global Connector style only. Push the connector toward the tube in order to release the pressure. Press and hold down the release mechanism, and pull the connector straight out.
  8. This step applies to the TI Loc style only. Push the connector toward the tube in order to release the pressure. Release the redundant latch (1) with two fingers or a flat bladed tool. Then press and hold down the bottom release mechanism (2) and pull the connector straight out.
  9. This step applies to the Safe Lock style only. Push the connector toward the tube in order to release the pressure. Release the second latch (1) with two fingers. Then press and hold down the bottom release mechanism (2) and pull the connector straight out.
  10. This step applies to the Plastic Connector style 8, push the connector toward the tube in order to release the pressure. Press the latch (1) inward in order to release the pipe, while pulling the connector (2) straight out.
  11. Using a clean shop towel, wipe off the male pipe end.
  12. Inspect both ends of the fitting for dirt and burrs.
  13. Clean or replace components as necessary.
  1. Apply a few drops of clean engine oil to the male pipe end.
  2. Push both sides of the quick-connect fitting together in order to cause the retaining feature to snap into place.
  3. Pull on both sides of the quick-connect fitting to make sure the connection is secure.
  4. Insert the tube in the connector until the retainer snaps in place.
  5. Push down on the redundant latch (1) until it is fully engaged and snapped into position.
  6. Insert the tube in the connector until the retainer snaps in place.
  7. Push down on the second latch (1) in order to secure the connection.
  8. For the plastic connector type 8, depress the latch (1) while inserting the connector (3) on to the pipe (2).
  9. Move the latch (1) upward in order to secure the connection.
  10. Inspect for leaks using the following procedure: Turn the ignition ON, with the engine OFF for 2 seconds. Turn the ignition OFF, for 10 seconds. Turn the ignition ON, with the engine OFF for 2 seconds. Turn the ignition OFF. Inspect for leaks.

Fuel Tank Draining

Special Tools

  1. J 36850 Transjel Lubricant
  2. J 45004 Fuel Tank Drain Hose
WARNINGNever drain or store fuel in an open container. Always use an approved fuel storage container in order to reduce the chance of fire or explosion.
WARNINGPlace a dry chemical (Class B) fire extinguisher nearby before performing any on-vehicle service procedures. Failure to follow these precautions may result in personal injury.
  1. Raise and Support the Vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle)
  2. Loosen the lower fill hose clamp in order to separate the fill hose from the fuel tank (1).
  3. Insert the J 45004 fuel tank drain hose into the fuel tank (1) until the hose reaches the bottom of the fuel tank.
  4. Use a hand or air operated pump device in order to drain as much fuel from the fuel tank as possible.

Scheme 50

Scheme 50: Fuel Tank Protector Replacement
Scheme 50: Fuel Tank Protector Replacement
CalloutComponent Name
Preliminary Procedure Remove the left fuel tank strap. Refer to Fuel Tank Replacement (With AWD) , Fuel Tank Replacement (With FWD) .
1Fuel Tank Protector Retainers (Qty: 3)
2Fuel Tank Protector

Fuel Tank Protector Replacement

  1. Relieve the system fuel pressure. Refer to «Fuel Pressure Relief»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions__fuel-pressure-relief)
  2. Drain the fuel tank. Refer to «Fuel Tank Draining»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions__fuel-tank-draining) .
  3. Disconnect the evaporative emission and fuel pipes (1). Refer to «Plastic Collar Quick Connect Fitting Service»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  4. Disconnect the fuel pressure sensor electrical connector (2).
  5. Loosen the hose clamps (1) and remove the filler tube (2).
  6. Disconnect the fuel tank harness electrical connector (1).
  7. Support the fuel tank with a suitable jack.
  8. Remove the fuel tank strap bolts (1).
  9. Swing the fuel tank straps (1) out of the way.
  10. Remove the fuel tank (1).
  11. Remove the following components if replacing just the fuel tank. Fuel tank fuel pump module. Refer to «Fuel Tank Fuel Pump Module Replacement (With AWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions__fuel-tank-fuel-pump-module-replacement) , «Fuel Tank Fuel Pump Module Replacement (LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions__fuel-tank-fuel-pump-module-replacement) . Evaporative emission carbon canister. Refer to «Evaporative Emission Canister Replacement (With AWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) , «Evaporative Emission Canister Replacement (With FWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) . Transfer components as necessary.
  1. Install the following components if fuel tank replacement was necessary: Fuel tank fuel pump module. Refer to «Fuel Tank Fuel Pump Module Replacement (With AWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions__fuel-tank-fuel-pump-module-replacement) , «Fuel Tank Fuel Pump Module Replacement (LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions__fuel-tank-fuel-pump-module-replacement) . Evaporative emission carbon canister. Refer to «Evaporative Emission Canister Replacement (With AWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) , «Evaporative Emission Canister Replacement (With FWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  2. Use a suitable jack and install the fuel tank (1).
  3. Reposition the fuel tank straps (1).
  4. Install the fuel tank strap bolts (1) and tighten to 20 N.m (15 lb ft).
  5. Connect the fuel tank harness electrical connector (1).
  6. Install the filler tube (2) and tighten the hose clamps (1) to 4Y(35 lb in).
  7. Connect the evaporative emission line (3). Refer to «Plastic Collar Quick Connect Fitting Service»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions)
  8. Connect the evaporative emission and fuel pipes (1). Refer to «Plastic Collar Quick Connect Fitting Service»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  9. Connect the fuel pressure sensor electrical connector (2).
  10. Refill the fuel tank.
  11. Inspect for fuel leaks.
WARNINGAlways wear safety goggles when working with fuel in order to protect the eyes from fuel splash.
  1. Turn the ignition OFF.
  2. Disconnect the negative battery cable. Refer to «Battery Negative Cable Disconnection and Connection»(/buick/lacrosse/ii-2009-2013/remont/charging-system/#battery-charging-system-and-starting-system-except-hybrid) .
  3. Relieve the fuel system pressure. Refer to «Fuel Pressure Relief»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions__fuel-pressure-relief) .
  4. Drain the fuel tank. Refer to «Fuel Tank Draining»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions__fuel-tank-draining) .
  5. Remove the propeller shaft. Refer to «Propeller Shaft Replacement»(/buick/lacrosse/ii-2009-2013/remont/driveshaft-universal-joints/#propeller-shaft) .
  6. Remove the exhaust system. Refer to «Exhaust Muffler Replacement (Single)»(/buick/lacrosse/ii-2009-2013/remont/exhaust/#engine-exhaust-system) , «Exhaust Muffler Replacement (LFX)»(/buick/lacrosse/ii-2009-2013/remont/exhaust/#engine-exhaust-system)
  7. Remove the rear wheelhouse panel liner. Refer to «Rear Wheelhouse Panel Liner Replacement»(/buick/lacrosse/ii-2009-2013/remont/frames-subframes-crossmembers/#frame-and-underbody) .
  8. Disconnect the fuel tank fuel pump module wiring harness (2).
  9. Unclip the fuel tank module wiring harness from the chassis (1).
  10. Disconnect the fuel tank filler vent pipe from the fuel tank filler vent pipe (3). Refer to «Plastic Collar Quick Connect Fitting Service»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-24l-repair-instructions) .
  11. Disconnect the fuel tank filler tube (2) from the fuel tank.
  12. Disconnect the evaporative emission purge and fuel feed pipes (1). Refer to «Plastic Collar Quick Connect Fitting Service»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  13. Disconnect the fuel pressure sensor harness connector (2).
  14. Disconnect the wiring harness connector from the fuel pipe.
  15. Position a suitable hydraulic lift below the fuel tank.
  16. Remove both fuel tank strap fasteners (3).
  17. Remove both fuel tank straps (2) from the fuel tank (1).
  18. With the aid of an assistant, lower the hydraulic lift to remove the fuel tank from the vehicle.
  19. Remove the fuel tank from the hydraulic lift.

Scheme 51

Scheme 51: Installation Procedure
Scheme 51: Installation Procedure

Scheme 52

Scheme 52
Scheme 52

Scheme 53

Scheme 53
Scheme 53

Scheme 54

Scheme 54
Scheme 54

Scheme 55

Scheme 55
Scheme 55
  1. If replacing the fuel tank transfer the following components. The evaporative emission canister (2). Refer to «Evaporative Emission Canister Replacement (With AWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) , «Evaporative Emission Canister Replacement (With FWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) . The evaporative emission canister purge pipe (1). Refer to «Evaporative Emission Canister Purge Pipe Replacement (With AWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) , «Evaporative Emission Canister Purge Pipe Replacement (With FWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) The fuel tank feed pipe (2). Refer to «Fuel Feed Pipe Replacement (With AWD at Tank)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) , «Fuel Feed Pipe Replacement (LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) The sender assembly (1). Refer to «Fuel Sender Assembly Replacement (With AWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions__fuel-sender-assembly-replacement-with-awd) The tank fuel pump module (1). Refer to «Fuel Tank Fuel Pump Module Replacement (With AWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions__fuel-tank-fuel-pump-module-replacement) , «Fuel Tank Fuel Pump Module Replacement (LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions__fuel-tank-fuel-pump-module-replacement) The fuel tank wiring harness.
  2. With the aid of an assistant, position the fuel tank on a hydraulic lift and raise into vehicle position.
  3. Install both fuel tank straps (2) to the fuel tank (1) and tighten the fasteners (3) to 27 N.m (20 lb ft).
  4. Remove the hydraulic lift from the fuel tank.
  5. Connect the evaporative emission purge and fuel pipes (1). Refer to «Plastic Collar Quick Connect Fitting Service»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-24l-repair-instructions) .
  6. Connect the fuel pressure sensor harness connector (2).
  7. Install the fuel tank filler tube (2) and tighten the clamp (1).
  8. Connect the fuel tank filler vent pipe to the fuel tank filler vent pipe (3). Refer to «Plastic Collar Quick Connect Fitting Service»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  9. Connect the fuel tank fuel pump module wiring harness (2).
  10. Clip the fuel tank module wiring harness to the chassis (1).
  11. Install the rear wheelhouse panel liner. Refer to «Rear Wheelhouse Panel Liner Replacement»(/buick/lacrosse/ii-2009-2013/remont/frames-subframes-crossmembers/#frame-and-underbody) .
  12. Install the exhaust system. Refer to «Exhaust Muffler Replacement (Single)»(/buick/lacrosse/ii-2009-2013/remont/exhaust/#engine-exhaust-system) , «Exhaust Muffler Replacement (LFX)»(/buick/lacrosse/ii-2009-2013/remont/exhaust/#engine-exhaust-system) .
  13. Install the propeller shaft. Refer to «Propeller Shaft Replacement»(/buick/lacrosse/ii-2009-2013/remont/driveshaft-universal-joints/#propeller-shaft) .
  14. Connect the negative battery cable. Refer to «Battery Negative Cable Disconnection and Connection»(/buick/lacrosse/ii-2009-2013/remont/charging-system/#battery-charging-system-and-starting-system-except-hybrid) .
  15. Refuel the fuel tank.

Fuel Tank Fuel Pump Module Replacement (LFW or LFX)

Special Tools

J 45722 Fuel Sender Lock Ring Wrench

For equivalent regional tools, refer to Special Tools (Diagnostic Tools)

  1. Remove the fuel tank. Refer to «Fuel Tank Replacement (With AWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) , «Fuel Tank Replacement (With FWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  2. Disconnect the fuel pump electrical connector (1) and the quick connects (2). Refer to «Plastic Collar Quick Connect Fitting Service»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  3. Use the J 45722 wrench by turning counter clockwise and remove the lock ring (1).
  4. Remove the fuel tank module (1) and the O-ring (2).
  1. Install a NEW seal (2) and the fuel tank module (1).
  2. Use the J 45722 wrench by turning clockwise and install the lock ring (1).
  3. Connect the fuel pump electrical connector (1) and the quick connects (2). Refer to «Plastic Collar Quick Connect Fitting Service»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  4. Install the fuel tank. Refer to «Fuel Tank Replacement (With AWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) , «Fuel Tank Replacement (With FWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .

Fuel Tank Fuel Pump Module Replacement (With AWD)

Special Tools

CH-45722 Fuel Sender Lock Ring Wrench

For equivalent regional tools, refer to Special Tools (Diagnostic Tools) .

  1. Remove the fuel tank. Refer to «Fuel Tank Replacement (With AWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) , «Fuel Tank Replacement (With FWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  2. Remove the fuel sender assembly from the fuel tank. Refer to «Fuel Sender Assembly Replacement (With AWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions__fuel-sender-assembly-replacement-with-awd) .
  3. Disconnect the fuel feed pipe (2) from the fuel pump module (1). Refer to «Plastic Collar Quick Connect Fitting Service»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  4. Disconnect the fuel tank module harness connectors.
  5. Use the CH-45722 fuel sender lock ring wrench (1), to remove the fuel sender lock ring (2) from the fuel pump module.
  6. Carefully lift the fuel pump module (1) while guiding the fuel tank crossover pipe (2) from the fuel tank (3).
  7. Remove and DISCARD the fuel pump module O-ring.
  1. Install a NEW the fuel pump O-ring.
  2. Carefully lower the fuel pump module (2) while guiding the fuel tank crossover pipe (2) into the fuel tank (3).
  3. Use the CH-45722 fuel sender lock ring wrench (1), to install the fuel sender lock ring (2).
  4. Connect the fuel tank module harness connectors.
  5. Connect the fuel feed pipe (2) from the fuel pump module. Refer to «Plastic Collar Quick Connect Fitting Service»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  6. Install the fuel sender assembly to the fuel tank. Refer to «Fuel Sender Assembly Replacement (With AWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions__fuel-sender-assembly-replacement-with-awd) .
  7. Install the fuel tank. Refer to «Fuel Tank Replacement (With AWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) , «Fuel Tank Replacement (With FWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .

Scheme 56

Scheme 56: Fuel Pump Flow Control Module Replacement
Scheme 56: Fuel Pump Flow Control Module Replacement
CalloutComponent Name
Preliminary Procedure Remove the passenger rear side trim panel. Refer to Rear Compartment Side Trim Panel Replacement (without HP6) , Rear Compartment Side Trim Panel Replacement (HP6, Left Side) , Rear Compartment Side Trim Panel Replacement (HP6, Right Side) .
1Fuel Pump Flow Control Module Fastener (Qty: 3) CAUTION: Refer to Fastener Caution . Tighten 9 N.m (80 lb in)
2Fuel Pump Flow Control Module Procedure Disconnect the electrical connector. If replacing, reprogram the module. Refer to Control Module References .
CAUTION
Refer to Fastener Caution .

Fuel Pump Flow Control Module Replacement

Scheme 57

Scheme 57: Fuel Tank Pressure Sensor Replacement (LFW or LFX)
Scheme 57: Fuel Tank Pressure Sensor Replacement (LFW or LFX)
CalloutComponent Name
Preliminary Procedure Remove the fuel tank. Refer to Fuel Tank Replacement (With AWD) , Fuel Tank Replacement (With FWD) .
1Fuel Tank Pressure Sensor Procedure Disconnect the electrical connector. Release the retaining tab.

Fuel Tank Pressure Sensor Replacement (LFW or LFX)

Scheme 58

Scheme 58: Fuel Tank Filler Pipe Replacement
Scheme 58: Fuel Tank Filler Pipe Replacement
CalloutComponent Name
Preliminary Procedure Remove the filler pipe housing. Refer to Fuel Tank Filler Valve Housing Replacement .
1Filler Pipe Fastener (Qty: 2) CAUTION: Refer to Fastener Caution . Tighten 9 N.m (80 lb in)
2Rear Evaporative Emission Pipe Procedure Disconnect the quick connect fitting. Refer to Plastic Collar Quick Connect Fitting Service .
3Hose Clamp Tighten 4 N.m (35 lb in)
CAUTION
Refer to Fastener Caution .

Fuel Tank Filler Pipe Replacement

WARNINGFuel Vapors can collect while servicing fuel system parts in enclosed areas such as a trunk. To reduce the risk of fire and increased exposure to vapors: Use forced air ventilation such as a fan set outside of the trunk. Plug or cap any fuel system openings in order to reduce fuel vapor formation. Clean up any spilled fuel immediately. Avoid sparks and any source of ignition. Use signs to alert others in the work area that fuel system work is in process.
  1. Remove the fuel tank pump module. Refer to «Fuel Tank Fuel Pump Module Replacement (NT7)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-24l-repair-instructions__fuel-tank-fuel-pump-module-replacement) , «Fuel Tank Fuel Pump Module Replacement (NU6)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-24l-repair-instructions__fuel-tank-fuel-pump-module-replacement) .
  2. Using two flat-bladed tools, carefully pull both locking tabs (1) outward while simultaneously lifting the level sensor.
  3. Using a small bladed tool, gently release the retaining tabs on the electrical terminals (1) while simultaneously pulling the terminals out.
  4. Inspect the terminals for bending and reposition as necessary.
  1. Push in the electrical terminals (1) and ensure the terminals are secure.
  2. Carefully insert the level sensor until the locking tabs (1) snap into the locking position.
  3. Install the fuel tank pump module. Refer to «Fuel Tank Fuel Pump Module Replacement (NT7)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-24l-repair-instructions__fuel-tank-fuel-pump-module-replacement) , «Fuel Tank Fuel Pump Module Replacement (NU6)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-24l-repair-instructions__fuel-tank-fuel-pump-module-replacement) .
  1. Relieve the fuel system pressure. Refer to «Fuel Pressure Relief»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions__fuel-pressure-relief) .
  2. Disconnect the fuel feed pipe quick connect fitting (1). Refer to «Metal Collar Quick Connect Fitting Service»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions__metal-collar-quick-connect-fitting-service) .
  3. Disconnect the evaporative emission hose (1). Refer to «Plastic Collar Quick Connect Fitting Service»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  4. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
  5. Remove both AC evaporator thermal expansion valve heat and brake pipe shield fasteners (1).
  6. Remove the fuel feed pressure sensor. Refer to «Fuel Pressure Sensor Replacement - Fuel Feed Pipe»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  7. Disconnect the fuel feed pipe quick connect fitting (1) and the evaporative emission pipe (2). Refer to «Plastic Collar Quick Connect Fitting Service»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  8. Plug or cap the fuel feed pipe to prevent fuel loss or contamination.
  9. Disconnect the brake pipes from the plastic retainers.
  10. Remove the fuel feed and evaporative emission pipes (1) as an assembly from the vehicle.
  11. Separate the fuel feed pipe (1) from the evaporative emission pipe.
  1. Ensure that the fuel feed pipe and fittings are clean and dry prior to assembly.
  2. Install the fuel feed pipe (1) to the evaporative emission pipe.
  3. Install the fuel feed and evaporative emission pipes (1) as an assembly to the vehicle.
  4. Connect the brake pipes to the plastic retainers.
  5. Remove the plug or cap from the fuel feed pipe.
  6. Connect the fuel feed pipe quick connect fitting (1) and the evaporative emission pipe (2). Refer to «Plastic Collar Quick Connect Fitting Service»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  7. Install the fuel feed pressure sensor. Refer to «Fuel Pressure Sensor Replacement - Fuel Feed Pipe»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  8. Install both AC evaporator thermal expansion valve heat and brake pipe shield fasteners (1).
  9. Disconnect the evaporative emission hose (1). Refer to «Plastic Collar Quick Connect Fitting Service»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  10. Connect the fuel feed pipe quick connect fitting (1). Refer to «Metal Collar Quick Connect Fitting Service»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions__metal-collar-quick-connect-fitting-service) .
  11. Inspect for leaks using the following procedure: 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.

Scheme 59

Scheme 59: Fuel Pressure Sensor Replacement - Fuel Feed Pipe
Scheme 59: Fuel Pressure Sensor Replacement - Fuel Feed Pipe
CalloutComponent Name
Preliminary Procedures Relieve the fuel system pressure. Refer to Fuel Pressure Relief . Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
1Fuel Pressure Sensor CAUTION: Refer to Fastener Caution . Procedure Disconnect the electrical connector. Use a NEW O-ring whenever the sensor is removed. Tighten 9Y (80 lb in)
CAUTION
Refer to Fastener Caution .

Fuel Pressure Sensor Replacement - Fuel Feed Pipe

Scheme 60

Scheme 60: Fuel Feed Pipe Replacement (LFW or LFX)
Scheme 60: Fuel Feed Pipe Replacement (LFW or LFX)
CalloutComponent Name
Preliminary Procedures Relieve the fuel system pressure. Refer to Fuel Pressure Relief . Remove the intake manifold cover. Refer to Intake Manifold Cover Replacement . Remove the fuel pipe shield. Refer to Fuel Pipe Shield Replacement (LFW or LFX) . Disconnect the fuel feed line quick connect. Refer to Metal Collar Quick Connect Fitting Service .
1Fitting (Qty: 1) CAUTION: Refer to Fastener Caution . Tighten 28 N.m (20 lb ft)
2Bolt (Qty: 2) Tighten 50 N.m (28 lb ft)
3Fuel Feed Pipe Procedure DISCARD the pipe when removed, and install a NEW pipe. Ensure that the high pressure fuel pipe, and fuel pump fittings are clean and dry prior to assembly. Pressure up the fuel system and check for leaks.
CAUTION
Refer to Fastener Caution .

Fuel Feed Pipe Replacement (LFW or LFX)

Scheme 61

Scheme 61: Fuel Feed Pipe Replacement (With AWD at Tank)
Scheme 61: Fuel Feed Pipe Replacement (With AWD at Tank)
CalloutComponent Name
Preliminary Procedure Remove the fuel tank. Refer to Fuel Tank Replacement (With AWD) , Fuel Tank Replacement (With FWD) .
1Fuel Feed Pipe Procedure Disconnect the fuel feed pipe from the fuel tank retainer. Disconnect the fuel feed pipe from the fuel pump module. Refer to Plastic Collar Quick Connect Fitting Service .

Fuel Feed Pipe Replacement (With AWD at Tank)

Fuel System Cleaning

Note. When flushing the fuel tank, treat the fuel and water mixture as a hazardous material. Handle the material in accordance with all local, state and federal laws and regulations.

Note. Whenever the fuel tank is cleaned, inspect the fuel pump fuel strainer. If the fuel pump fuel strainer is contaminated, replace the fuel pump fuel strainer and inspect the fuel pump.

Note. Always maintain cleanliness when servicing fuel system components.

  1. Remove the fuel tank fuel pump module. Refer to «Fuel Tank Fuel Pump Module Replacement (With AWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions__fuel-tank-fuel-pump-module-replacement) , «Fuel Tank Fuel Pump Module Replacement (LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions__fuel-tank-fuel-pump-module-replacement) .
  2. Inspect the fuel pump inlet for dirt and debris. If dirt and debris are found, replace the fuel pump.
  3. Flush 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 ensure that the removal of the water from the fuel tank is complete.
  5. Allow tank to dry completely before reassembly.
  6. Install the fuel tank fuel pump module. Refer to «Fuel Tank Fuel Pump Module Replacement (With AWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions__fuel-tank-fuel-pump-module-replacement) , «Fuel Tank Fuel Pump Module Replacement (LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions__fuel-tank-fuel-pump-module-replacement) .

Scheme 62

Scheme 62: Fuel Pressure Sensor Replacement - Fuel Injection Fuel Rail (LFW or LFX)
Scheme 62: Fuel Pressure Sensor Replacement - Fuel Injection Fuel Rail (LFW or LFX)
CalloutComponent Name
Preliminary Procedure Relieve the fuel system pressure. Refer to Fuel Pressure Relief . Remove the fuel pipe shield. Refer to Fuel Pipe Shield Replacement (LFW or LFX) .
1Fuel Injection Fuel Rail Fuel Pressure Sensor CAUTION: Refer to Fastener Caution . Procedure Disconnect the electrical connector. Tighten 33 N.m (25 lb ft)
CAUTION
Refer to Fastener Caution .

Fuel Pressure Sensor Replacement - Fuel Injection Fuel Rail (LFW or LFX)

Fuel Injection Fuel Rail Assembly Replacement - Bank 1 (LFW or LFX)

Special Tools

EN-49248 Injector Rail Assembly Remover

For equivalent regional tools, refer to Special Tools (Diagnostic Tools) .

  1. Relieve the fuel system pressure. Refer to «Fuel Pressure Relief»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions__fuel-pressure-relief) .
  2. Remove the fuel pipe shield. Refer to «Fuel Pipe Shield Replacement (LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  3. Remove the intake manifold. Refer to «Intake Manifold Replacement (LF1, LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/mechanical/#engine-mechanical-36l-repair-instructions-on-vehicle) .
  4. Remove the fuel feed intermediate pipe. Refer to «Fuel Feed Intermediate Pipe Replacement (LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  5. Remove the foam insulator from the fuel rails.
  6. Cut the plastic tie strap (1).
  7. Disconnect the fuel pressure sensor electrical connector (2).
  8. Remove the fuel pressure sensor (3).
  9. Remove the bank 2 fuel rail fasteners (1).
  10. Remove the bank 1 fuel rail fasteners (1) for clearance purposes.
  11. Using the EN-49248-4 hook, raise the fuel rail (1) as an assembly.
  12. Once the fuel rail is free, remove the EN-49248 special tool.
  13. Slide the fuel rail (1) toward the front of the engine approximately 1 inch (25.4 mm), in order to clear the center injector bore.
  14. Once the fuel rail is removed, remove the fuel injectors and rebuild them. Refer to «Fuel Rail and Injectors Cleaning and Inspection (LF1, LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/mechanical/#engine-mechanical-36l-repair-instructions-off-vehicle__fuel-rail-and-injectors-cleaning-and) .
  1. Slide the fuel rail (1) toward the rear of the engine approximately 1 inch (25.4 mm), in order to align the center injector bore.
  2. Hand tighten the two outer fuel rail fasteners to seat the injectors.
  3. Start and hand tighten the remaining fuel rail fasteners.
  4. Tighten the fuel rail fasteners in the sequence shown above: First pass 12 N.m (106 lb in). Final pass 23 N.m (17 lb ft).
  5. Tighten the fuel pressure sensor (3) to 33 N.m (25 lb ft).
  6. Connect the fuel pressure sensor electrical connector (2) and secure it with a new plastic zip tie.
  7. Install the fuel feed intermediate pipe. Refer to «Fuel Feed Intermediate Pipe Replacement (LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  8. Inspect for fuel leaks using the following procedure: 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.
  9. Install the foam insulator to the fuel rails.
  10. Install the intake manifold. Refer to «Intake Manifold Replacement (LF1, LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/mechanical/#engine-mechanical-36l-repair-instructions-on-vehicle) .
  11. Install the fuel pipe shield. Refer to «Fuel Pipe Shield Replacement (LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  12. Install the low side fuel pressure service port cap.
  13. Install the fuel tank cap.

Fuel Injection Fuel Rail Assembly Replacement - Bank 2 (LFW or LFX)

Special Tools

EN-49248 Injector Rail Assembly Remover

For equivalent regional tools, refer to Special Tools (Diagnostic Tools) .

  1. Relieve the fuel system pressure. Refer to «Fuel Pressure Relief»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions__fuel-pressure-relief) .
  2. Remove the fuel pipe shield. Refer to «Fuel Pipe Shield Replacement (LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  3. Remove the intake manifold. Refer to «Intake Manifold Replacement (LF1, LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/mechanical/#engine-mechanical-36l-repair-instructions-on-vehicle) .
  4. Remove the fuel feed intermediate pipe. Refer to «Fuel Feed Intermediate Pipe Replacement (LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  5. Remove the foam insulator from the fuel rails.
  6. Remove the bank 1 fuel rail fasteners (1).
  7. Remove the bank 2 fuel rail fasteners (1) for clearance purposes.
  8. Using the EN-49248-4 hook, raise the fuel rail (1) as an assembly.
  9. Once the fuel rail is free, remove the EN-49248 remover.
  10. Slide the fuel rail (1) toward the rear of the engine approximately 1 inch (25.4mm), in order to clear the center injector bore.
  11. Once the fuel rail is removed, remove the fuel injectors and rebuild them. Refer to «Fuel Rail and Injectors Cleaning and Inspection (LF1, LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/mechanical/#engine-mechanical-36l-repair-instructions-off-vehicle__fuel-rail-and-injectors-cleaning-and) .
  1. Slide the fuel rail (1) toward the front of the engine approximately 1 inch (25.4mm), in order to align the center injector bore.
  2. Hand tighten the two outer fuel rail fasteners to seat the injectors.
  3. Start and hand tighten the remaining fuel rail fasteners.
  4. Tighten the fuel rail fasteners in the sequence shown above: Tighten the Bank 1 fuel rail bolts first pass to 12 N.m (106 lb in). Tighten the Bank 1 fuel rail bolts a final pass to 23 N.m (17 lb ft).
  5. Install the fuel feed intermediate pipe. Refer to «Fuel Feed Intermediate Pipe Replacement (LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  6. Inspect for fuel leaks using the following procedure: 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.
  7. Install the foam insulator to the fuel rails.
  8. Install the intake manifold. Refer to «Intake Manifold Replacement (LF1, LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/mechanical/#engine-mechanical-36l-repair-instructions-on-vehicle) .
  9. Install the fuel pipe shield. Refer to «Fuel Pipe Shield Replacement (LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  10. Install the low side fuel pressure service port cap.
  11. Install the fuel tank cap.

Scheme 63

Scheme 63: Fuel Feed Intermediate Pipe Replacement (LFW or LFX)
Scheme 63: Fuel Feed Intermediate Pipe Replacement (LFW or LFX)
CalloutComponent Name
Preliminary Procedures Relieve the fuel system pressure. Refer to Fuel Pressure Relief . Remove the intake manifold cover. Refer to Intake Manifold Cover Replacement . Remove the fuel pipe shield. Refer to Fuel Pipe Shield Replacement (LFW or LFX) .
1Fitting (Qty: 3) CAUTION: Refer to Fastener Caution . Tighten Tighten the fittings in sequence as numbered: 1, 2, 3 First Pass 15 N.m (11 lb ft) Second Pass 30 N.m (22 lb ft)
2Fuel Feed Intermediate Pipe Procedure Discard the pipe when removed and install a NEW pipe. Lubricate the pipes with silicon free engine oil. Refer to Adhesives, Fluids, Lubricants, and Sealers . Pressure up the fuel system and check for leaks.
CAUTION
Refer to Fastener Caution .

Fuel Feed Intermediate Pipe Replacement (LFW or LFX)

Scheme 64

Scheme 64: Fuel Pipe Shield Replacement (LFW or LFX)
Scheme 64: Fuel Pipe Shield Replacement (LFW or LFX)
CalloutComponent Name
Preliminary Procedure Remove the intake manifold cover. Refer to Intake Manifold Cover Replacement .
1Bolt CAUTION: Refer to Fastener Caution . Tighten 10 N.m (89 lb in)
2Retainer
3Fuel Pipe Shield
CAUTION
Refer to Fastener Caution .

Fuel Pipe Shield Replacement (LFW or LFX)

Fuel Pump Replacement

Special Tools

EN-48896 High Pressure Fuel Pump Installation Alignment Gauge

For equivalent regional tools, refer to Special Tools (Diagnostic Tools) .

  1. Relieve the low and high side fuel system pressure. Refer to «Fuel Pressure Relief»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions__fuel-pressure-relief) .
  2. Remove the high pressure fuel pump shield. Refer to «Fuel Pipe Shield Replacement (LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  3. Disconnect the engine wiring harness electrical connector from the high pressure fuel pump.
  4. Remove the low pressure feed pipe. Refer to «Fuel Feed Pipe Replacement (With AWD at Tank)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) , «Fuel Feed Pipe Replacement (LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  5. Remove the high pressure pipe. Discard the pipe. Refer to «Fuel Feed Intermediate Pipe Replacement (LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  6. Remove and discard the high pressure fuel pump bolts (1).
  7. Remove the high pressure fuel pump (2).
  8. Remove and discard the high pressure fuel pump O-ring (3).
  9. Remove and discard the high pressure fuel pump gasket (4).
  10. Remove the high pressure fuel pump roller lifter (5).
  1. Use the EN-48896 alignment gauge to ensure that the camshaft lobe is in the base circle position. At base circle the tool will be flush with the head.
  2. Lubricate the high pressure fuel pump cylinder head bore and roller lifter with camshaft prelube. Refer to «Adhesives, Fluids, Lubricants, and Sealers»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-specifications__adhesives-fluids-lubricants-and-sealers) .
  3. Install the high pressure fuel pump roller lifter (5).
  4. Install a NEW high pressure fuel pump O-ring (3).
  5. Position the NEW high pressure fuel pump gasket (4) and bolts (1) to the fuel pump.
  6. Install the high pressure fuel pump (2). Force will be required while hand tightening the bolts.
  7. Tighten the high pressure fuel pump retaining bolts to 15 N.m (11 lb ft).
  8. Ensure the high pressure fuel pump and fuel rail fittings are clean prior to assembly.
  9. Install a NEW high pressure fuel pipe. Refer to «Fuel Feed Intermediate Pipe Replacement (LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  10. Install the fuel feed pipe to the high pressure fuel pump. Refer to «Fuel Feed Pipe Replacement (With AWD at Tank)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) , «Fuel Feed Pipe Replacement (LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  11. Connect the high pressure fuel pump wiring harness.
  12. Install the fuel tank cap.
  13. Inspect for leaks using the following procedure: 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 pressure relief cap to the fuel feed pipe.
  15. Install the high pressure fuel pump shield. Refer to «Fuel Pipe Shield Replacement (LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .

Scheme 65

Scheme 65: Evaporative Emission Canister Purge Solenoid Valve Replacement (LFW or LFX)
Scheme 65: Evaporative Emission Canister Purge Solenoid Valve Replacement (LFW or LFX)
CalloutComponent Name
Preliminary Procedure Remove the intake manifold cover. Refer to Intake Manifold Cover Replacement .
1Bolt CAUTION: Refer to Fastener Caution . Tighten 10 N.m (89 lb in)
2Evaporative Emission Canister Purge Solenoid Valve Procedure Disconnect the EVAP canister purge solenoid harness connector. Install a NEW O-ring.
CAUTION
Refer to Fastener Caution .

Evaporative Emission Canister Purge Solenoid Valve Replacement (LFW or LFX)

Scheme 66

Scheme 66: Evaporative Emission Canister Vent Solenoid Valve Replacement
Scheme 66: Evaporative Emission Canister Vent Solenoid Valve Replacement
CalloutComponent Name
Preliminary Procedure Remove the carbon canister. Refer to Evaporative Emission Canister Replacement (With AWD) , Evaporative Emission Canister Replacement (With FWD) .
1Evaporative Canister Vent Solenoid Valve Procedure Disconnect the electrical connector.

Evaporative Emission Canister Vent Solenoid Valve Replacement

Scheme 67

Scheme 67: Evaporative Emission Canister Purge Pipe Replacement (With FWD)
Scheme 67: Evaporative Emission Canister Purge Pipe Replacement (With FWD)
CalloutComponent Name
Preliminary Procedure Remove the fuel tank. Refer to Fuel Tank Replacement (With AWD) , Fuel Tank Replacement (With FWD) .
1Evaporative Emission Canister Purge Pipe Procedure Disconnect the evaporative emission quick connects. Refer to Plastic Collar Quick Connect Fitting Service .

Evaporative Emission Canister Purge Pipe Replacement (With FWD)

Scheme 68

Scheme 68: Evaporative Emission Canister Purge Pipe Replacement (With AWD)
Scheme 68: Evaporative Emission Canister Purge Pipe Replacement (With AWD)
CalloutComponent Name
Preliminary Procedure Remove the fuel tank. Refer to Fuel Tank Replacement (With AWD) , Fuel Tank Replacement (With FWD) .
1Evaporative Emission Canister Purge Pipe Procedure Disconnect the evaporative emission canister purge pipe from the fuel tank retainers. Disconnect the evaporative emission canister purge pipe from the evaporative emission canister. Refer to Plastic Collar Quick Connect Fitting Service .

Evaporative Emission Canister Purge Pipe Replacement (With AWD)

Scheme 69

Scheme 69: Evaporative Emission Canister Vent Front Pipe Replacement
Scheme 69: Evaporative Emission Canister Vent Front Pipe Replacement
CalloutComponent Name
Preliminary Procedure Remove the fuel tank. Refer to Fuel Tank Replacement (With AWD) , Fuel Tank Replacement (With FWD) .
1Evaporative Emission Canister Vent Front Pipe Procedure Disconnect the evaporative emission quick connects. Refer to Plastic Collar Quick Connect Fitting Service .

Evaporative Emission Canister Vent Front Pipe Replacement

Scheme 70

Scheme 70: Evaporative Emission Canister Replacement (With FWD)
Scheme 70: Evaporative Emission Canister Replacement (With FWD)
CalloutComponent Name
Preliminary Procedure Remove the fuel tank. Refer to Fuel Tank Replacement (With AWD) , Fuel Tank Replacement (With FWD) .
1Evaporative Emission Hose (Qty: 2) Procedure Disconnect the quick connects. Refer to Plastic Collar Quick Connect Fitting Service .
2Evaporative Emission Canister Procedure Disconnect the electrical connector. Release the retaining tab.

Evaporative Emission Canister Replacement (With FWD)

Scheme 71

Scheme 71: Evaporative Emission Canister Replacement (With AWD)
Scheme 71: Evaporative Emission Canister Replacement (With AWD)
CalloutComponent Name
Preliminary Procedure Lower the fuel tank enough to allow evaporative emission canister removal. Refer to Fuel Tank Replacement (With AWD) , Fuel Tank Replacement (With FWD) .
1Evaporative Emission Canister Retaining Tab Procedure Depress the retaining tab in order to release the evaporative emission canister from the fuel tank.
2Evaporative Emission Canister Procedure Release the evaporative emission vent pipe from the evaporative emission canister. Refer to Plastic Collar Quick Connect Fitting Service . Release the evaporative emission canister purge pipe from the evaporative emission canister. Refer to Plastic Collar Quick Connect Fitting Service . Disconnect the evaporative emission canister solenoid wiring harness.

Evaporative Emission Canister Replacement (With AWD)

Evaporative Emission System Cleaning

Special Tools

GE 41413-200 Evaporative Pressure and Purge Station

For equivalent regional tools, refer to Special Tools (Diagnostic Tools) .

Inspection Procedure

CAUTIONUse the Evaporative Emission (EVAP) System Tester (EEST) GE 41413-A in order to provide a clean, dry, low pressure nitrogen gas source. Do not substitute any other pressurized source, gas or otherwise. Damage may result to the EVAP system, test equipment or cause a safety risk.
  1. Turn OFF the ignition.
  2. Remove the EVAP canister purge valve. Refer to «Evaporative Emission Canister Purge Solenoid Valve Replacement (LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  3. Lightly tap the EVAP canister purge valve on a hard surface.
  4. Inspect for carbon particles exiting either of the vacuum ports. If no carbon particles were detected, but a blockage was detected during a diagnostic procedure, install the original EVAP canister purge valve. Continue with the cleaning procedure. If carbon particles are found during the inspection procedure, continue with the cleaning procedure. If a diagnostic procedure directed you to replace the EVAP canister purge valve and no carbon particles were detected, replace the EVAP canister purge valve. Return to the published service procedure.

Cleaning Procedure

  1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
  2. Remove the EVAP canister. Refer to «Evaporative Emission Canister Replacement (With AWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) , «Evaporative Emission Canister Replacement (With FWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  3. Turn OFF the main valve on the GE 41413-200 station.
  4. Disconnect the hose from the diagnostic station pressure regulator.
  5. Using a section of vacuum hose, connect one end onto the EVAP pressure/purge diagnostic station pressure regulator.
  6. Connect the other end of the vacuum hose to the canister side of the purge pipe.
  7. Turn ON the main nitrogen cylinder valve and continue to discharge nitrogen for 15 seconds.
  8. If the nitrogen does not clear the blockage, replace the purge pipe.
  9. Return the EVAP pressure/purge diagnostic station to the stations original condition.
  10. Install a new EVAP canister. Refer to «Evaporative Emission Canister Replacement (With AWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) , «Evaporative Emission Canister Replacement (With FWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  11. Lower the vehicle.
  12. Install a new EVAP canister purge valve. Refer to «Evaporative Emission Canister Purge Solenoid Valve Replacement (LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  13. Return to the diagnostic table that sent you here.
  1. Remove the intake manifold. Refer to «Intake Manifold Replacement (LF1, LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/mechanical/#engine-mechanical-36l-repair-instructions-on-vehicle) .
  2. Disconnect the engine wiring harness electrical connector(s) (1) from the ignition coil(s) (4).
  3. Remove the ignition coil bolt(s).
  4. Remove the ignition coil(s).
  1. Install the ignition coil(s).
  2. Install the ignition coil bolt(s). Tighten Tighten the bolt(s) to 10 N.m (89 lb in).
  3. Connect the engine wiring harness electrical connector(s) (1) to the ignition coil(s) (4).
  4. Install the intake manifold. Refer to «Intake Manifold Replacement (LF1, LFW or LFX)»(/buick/lacrosse/ii-2009-2013/remont/mechanical/#engine-mechanical-36l-repair-instructions-on-vehicle) .
  1. Remove the intake manifold cover. Refer to «Intake Manifold Cover Replacement»(/buick/lacrosse/ii-2009-2013/remont/mechanical/#engine-mechanical-36l-repair-instructions-on-vehicle) .
  2. Disconnect the engine wiring harness electrical connector(s) (5) from the ignition coil(s) (4).
  3. Remove the ignition coil bolt(s).
  4. Remove the ignition coil(s).
  1. Install the ignition coil(s).
  2. Install the ignition coil bolt(s). Tighten Tighten the bolt(s) to 10 N.m (89 lb in).
  3. Connect the engine wiring harness electrical connector(s) (5) to the ignition coil(s) (4).
  4. Install the intake manifold cover. Refer to «Intake Manifold Cover Replacement»(/buick/lacrosse/ii-2009-2013/remont/mechanical/#engine-mechanical-36l-repair-instructions-on-vehicle) .

Spark Plug Usage

  1. Ensure that the correct spark plug is installed. An incorrect spark plug causes driveability conditions. Refer to the Electronic Parts Catalog.
  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 for evidence of improper arcing. Measure the gap between the center electrode (4) and the side electrode (3) terminals. Refer to «Ignition System Specifications»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-specifications__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»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-specifications__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 ignition coil(s). Refer to «Ignition Coil Replacement - Bank 1»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) , and/or «Ignition Coil Replacement - Bank 2»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  2. Use compressed air in order to remove debris from the spark plug cavity.
  3. Remove the spark plug.
  1. Ensure that the spark plug gap is equivalent to the spark plug gap specification. Refer to «Ignition System Specifications»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-specifications__ignition-system-specifications) .
  2. Install the spark plug and tighten to 18 N.m (13 lb ft).
  3. Install the ignition coil(s). Refer to «Ignition Coil Replacement - Bank 1»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) , and/or «Ignition Coil Replacement - Bank 2»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .

Scheme 72

Scheme 72: Crankshaft Position Sensor Replacement
Scheme 72: Crankshaft Position Sensor Replacement
CalloutComponent Name
Preliminary Procedures If equipped with AWD, remove the right side catalytic converter. Refer to Catalytic Converter Replacement - Right Side (LFX-Rear) . Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
1Bolt CAUTION: Refer to Fastener Caution . Tighten 10 N.m (89 lb in)
2Bolt Tighten 58 N.m (42 lb ft)
3Exhaust Manifold Lower Heat Shield
4Bolt Tighten 10 N.m (89 lb in)
5Crankshaft Position Sensor Procedure Disconnect the crankshaft position sensor harness connector.
CAUTION
Refer to Fastener Caution .

Crankshaft Position Sensor Replacement

Scheme 73

Scheme 73: Camshaft Position Sensor Replacement - Bank 2 (Left Side) Exhaust
Scheme 73: Camshaft Position Sensor Replacement - Bank 2 (Left Side) Exhaust
CalloutComponent Name
Preliminary Procedure Remove the engine mount bracket. Refer to Engine Mount Bracket Replacement - Right Side .
1Camshaft Position Sensor Fastener CAUTION: Refer to Fastener Caution . Tighten 10 N.m (89 lb in)
2Camshaft Position Sensor Procedure Disconnect the electrical connector.
CAUTION
Refer to Fastener Caution .

Camshaft Position Sensor Replacement - Bank 2 (Left Side) Exhaust

Scheme 74

Scheme 74: Camshaft Position Sensor Replacement - Bank 2 (Left Side) Intake
Scheme 74: Camshaft Position Sensor Replacement - Bank 2 (Left Side) Intake
CalloutComponent Name
Preliminary Procedure Remove the engine mount bracket. Refer to Engine Mount Bracket Replacement - Right Side .
1Camshaft Position Sensor Fastener CAUTION: Refer to Fastener Caution . Tighten 10 N.m (89 lb in)
2Camshaft Position Sensor Procedure Disconnect the electrical connector.
CAUTION
Refer to Fastener Caution .

Camshaft Position Sensor Replacement - Bank 2 (Left Side) Intake

Scheme 75

Scheme 75: Camshaft Position Sensor Replacement - Bank 1 (Right Side) Exhaust
Scheme 75: Camshaft Position Sensor Replacement - Bank 1 (Right Side) Exhaust
CalloutComponent Name
Preliminary Procedure Remove the air cleaner assembly. Refer to Air Cleaner Assembly Replacement (LFW or LFX) .
1Camshaft Position Sensor Fastener CAUTION: Refer to Fastener Caution . Tighten 10 N.m (89 lb in)
2Camshaft Position Sensor Procedure Disconnect the electrical connector.
CAUTION
Refer to Fastener Caution .

Camshaft Position Sensor Replacement - Bank 1 (Right Side) Exhaust

Scheme 76

Scheme 76: Camshaft Position Sensor Replacement - Bank 1 (Right Side) Intake
Scheme 76: Camshaft Position Sensor Replacement - Bank 1 (Right Side) Intake
CalloutComponent Name
Preliminary Procedure Remove the air cleaner assembly. Refer to Air Cleaner Assembly Replacement (LFW or LFX) .
1Camshaft Position Sensor Fastener CAUTION: Refer to Fastener Caution . Tighten 10 N.m (89 lb in)
2Camshaft Position Sensor Procedure Disconnect the electrical connector.
CAUTION
Refer to Fastener Caution .

Camshaft Position Sensor Replacement - Bank 1 (Right Side) Intake

Scheme 77

Scheme 77: Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 1 (Right Side) Intake
Scheme 77: Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 1 (Right Side) Intake
CalloutComponent Name
Preliminary Procedures Remove the air cleaner assembly. Refer to Air Cleaner Assembly Replacement (LFW or LFX) .
1Camshaft Position Actuator Solenoid Valve Fastener CAUTION: Refer to Fastener Caution . Procedure Disconnect the electrical connector. Tighten 10 N.m (89 lb in)
2Camshaft Position Actuator Solenoid Valve
CAUTION
Refer to Fastener Caution .

Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 1 (Right Side) Intake

Scheme 78

Scheme 78: Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 1 (Right Side) Exhaust
Scheme 78: Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 1 (Right Side) Exhaust
CalloutComponent Name
Preliminary Procedures Remove the air cleaner assembly. Refer to Air Cleaner Assembly Replacement (LFW or LFX) .
1Camshaft Position Actuator Solenoid Valve Fastener CAUTION: Refer to Fastener Caution . Procedure Disconnect the electrical connector. Tighten 10 N.m (89 lb in)
2Camshaft Position Actuator Solenoid Valve
CAUTION
Refer to Fastener Caution .

Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 1 (Right Side) Exhaust

Scheme 79

Scheme 79: Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 2 (Left Side) Intake
Scheme 79: Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 2 (Left Side) Intake
CalloutComponent Name
Preliminary Procedure Remove the engine mount bracket. Refer to Engine Mount Bracket Replacement - Right Side .
1Camshaft Position Actuator Solenoid Valve Fastener CAUTION: Refer to Fastener Caution . Procedure Disconnect the electrical connector. Tighten 10 N.m (89 lb in)
2Camshaft Position Actuator Solenoid Valve
CAUTION
Refer to Fastener Caution .

Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 2 (Left Side) Intake

Scheme 80

Scheme 80: Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 2 (Left Side) Exhaust
Scheme 80: Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 2 (Left Side) Exhaust
CalloutComponent Name
Preliminary Procedure Remove the engine mount bracket. Refer to Engine Mount Bracket Replacement - Right Side .
1Camshaft Position Actuator Solenoid Valve Fastener CAUTION: Refer to Fastener Caution . Tighten 10 N.m (89 lb in)
2Camshaft Position Actuator Solenoid Valve Procedure Disconnect the electrical connector.
CAUTION
Refer to Fastener Caution .

Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 2 (Left Side) Exhaust

Scheme 81

Scheme 81: Knock Sensor Replacement - Bank 1
Scheme 81: Knock Sensor Replacement - Bank 1
CalloutComponent Name
Preliminary Procedures If equipped with AWD, remove the right side catalytic converter. Refer to Catalytic Converter Replacement - Right Side (LFX-Rear) . Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
1Bolt CAUTION: Refer to Fastener Caution . Tighten 10 N.m (89 lb in)
2Bolt Tighten 58 N.m (42 lb ft)
3Exhaust Manifold Lower Heat Shield
4Bolt Tighten 25 N.m (18 lb ft)
5Knock Sensor Procedure Disconnect the electrical connector.
CAUTION
Refer to Fastener Caution .

Knock Sensor Replacement - Bank 1

Scheme 82

Scheme 82: Knock Sensor Replacement - Bank 2
Scheme 82: Knock Sensor Replacement - Bank 2
CalloutComponent Name
Preliminary Procedure Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
1Knock Sensor Fastener CAUTION: Refer to Fastener Caution . Tighten 25 N.m (18 lb ft)
2Knock Sensor Procedure Disconnect the electrical connector.
CAUTION
Refer to Fastener Caution .

Knock Sensor Replacement - Bank 2

Scheme 83

Scheme 83: Air Cleaner Element Replacement (LFW or LFX)
Scheme 83: Air Cleaner Element Replacement (LFW or LFX)
CalloutComponent Name
Preliminary Procedure Disconnect the air cleaner outlet duct. Refer to Air Cleaner Outlet Duct Replacement (LFW or LFX) .
1Air Cleaner Assembly Fastener (Qty: 6) CAUTION: Refer to Fastener Caution .
2Air Cleaner Upper Cover Procedure From the left side of the air cleaner cover, tilt the cover upward. Disengage the upper cover tabs from the lower cover. Disconnect the electrical connectors.
3Air Cleaner Element
CAUTION
Refer to Fastener Caution .

Air Cleaner Element Replacement (LFW or LFX)

Scheme 84

Scheme 84: Air Cleaner Assembly Replacement (LFW or LFX)
Scheme 84: Air Cleaner Assembly Replacement (LFW or LFX)
CalloutComponent Name
Preliminary Procedure Disconnect the air cleaner outlet duct. Refer to Air Cleaner Outlet Duct Replacement (LFW or LFX) .
1Air Cleaner Assembly Procedure Remove the air cleaner housing from the retainers, while guiding the housing out of the inlet duct. Transfer parts as necessary.

Air Cleaner Assembly Replacement (LFW or LFX)

Scheme 85

Scheme 85: Air Cleaner Outlet Duct Replacement (LFW or LFX)
Scheme 85: Air Cleaner Outlet Duct Replacement (LFW or LFX)
CalloutComponent Name
Preliminary Procedure Remove the intake manifold cover. Refer to Intake Manifold Cover Replacement .
1Clamp (Qty: 2) CAUTION: Refer to Fastener Caution . Tighten 4 N.m (35 lb in)
2Air Cleaner Outlet Duct Procedure Disconnect the PCV tube from the air cleaner outlet duct. TIP: Use a flat-bladed tool in order to work out the PCV plastic connector.
CAUTION
Refer to Fastener Caution .

Air Cleaner Outlet Duct Replacement (LFW or LFX)

Fuel Sender Assembly Replacement (With AWD)

Special Tools

CH-48482 Fuel Sender Lock Ring Wrench

For equivalent regional tools, refer to Special Tools (Diagnostic Tools) .

  1. Remove the fuel tank. Refer to «Fuel Tank Replacement (With AWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) , «Fuel Tank Replacement (With FWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  2. Disconnect the fuel sender harness connector.
  3. Disconnect the evaporative emission canister vent pipe from the fuel sender assembly. Refer to «Plastic Collar Quick Connect Fitting Service»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  4. Use the CH-48482 fuel sender lock ring wrench, (1) to remove the fuel sender lock ring (2) from the fuel sender assembly.
  5. Carefully lift the fuel sender assembly (21) from the fuel tank. Do not disconnect the fuel crossover pipe at this time.
  6. Gently pull enough of the fuel crossover pipe (3) to disconnect it from the fuel sender assembly (1).
  7. Remove and DISCARD the fuel sender O-ring (2).
  1. Install a NEW the fuel sender O-ring (2).
  2. Connect the fuel sender to the fuel tank crossover fuel line (3).
  3. Carefully position the fuel sender assembly (1) into the fuel tank.
  4. Use the CH-48482 fuel sender lock ring wrench, (1) to install the fuel sender lock ring (2).
  5. Connect the evaporative emission canister vent pipe to the fuel sender assembly. Refer to «Plastic Collar Quick Connect Fitting Service»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .
  6. Connect the fuel sender harness connector.
  7. Install the fuel tank. Refer to «Fuel Tank Replacement (With AWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) , «Fuel Tank Replacement (With FWD)»(/buick/lacrosse/ii-2009-2013/remont/testing-diagnostics/#engine-controlsfuel-36l-repair-instructions) .

See also:
• Diagnostic Trouble Code (DTC) List - Vehicle
• Battery Negative Cable Disconnection and Connection
• Safety Glasses Warning
• Control Module References
• Cooling System Draining and Filling (Static Fill)
• Cooling System Draining and Filling (GE 47716)
• Fastener Caution
• Intake Manifold Cover Replacement
• Heated Oxygen and Oxygen Sensor Caution
• Adhesives, Fluids, Lubricants, and Sealers
• Lifting and Jacking the Vehicle
• Special Tools (Diagnostic Tools)
• Gasoline/Gasoline Vapors Warning
• Relieving Fuel Pressure Warning
• Propeller Shaft Replacement
• Exhaust Muffler Replacement (Single)
• Rear Wheelhouse Panel Liner Replacement
• Plastic Collar Quick Connect Fitting Service
• Rear Compartment Side Trim Panel Replacement (without HP6)
• Fuel Tank Filler Valve Housing Replacement
• Fuel Tank Fuel Pump Module Replacement (NT7)
• Cover and Plug Openings Caution
• Fuel Rail and Injectors Cleaning and Inspection (LF1, LFW or LFX)
• Ignition System Specifications
• Safety Glasses and Compressed Air Warning
• Throttle/Idle Learn
• Fuel Pressure Relief
• Fuel Tank Draining
• Fuel Tank Fuel Pump Module Replacement (With AWD)
• Fuel Sender Assembly Replacement (With AWD)
• Metal Collar Quick Connect Fitting Service

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