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Home >> Buick >> 2011 >> Lucerne CX >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Controls And Fuel - 3.9L - Repair Instructions >> Repair Instructions >> Fuel Tank Module Replacement (NU6) >> Removal Procedure
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Removal Procedure

WARNING:

In order to reduce the risk of fire and personal injury that may result from a fuel leak, always replace the fuel sender gasket when reinstalling the fuel sender assembly.

    Fig 1: Identifying Fuel Sender Access Hole Cover
    GM1671970Courtesy of GENERAL MOTORS COMPANY
  1. Relieve the fuel system pressure. Refer to Fuel Pressure Relief (CH 48027) , Fuel Pressure Relief (Without CH 48027) .
  2. Remove the rear compartment liner. Refer to Rear Compartment Trim Panel Replacement .
  3. Remove the fuel sender access hole cover bolts.
  4. Remove the fuel sender access hole cover.
  5. Fig 2: Fuel Feed Pipe, Evap Pipe, & Harness Connector
    GM1755108Courtesy of GENERAL MOTORS COMPANY
  6. Disconnect the fuel feed rear pipe quick connect fitting (3) from the sender. Refer to Plastic Collar Quick Connect Fitting Service .
  7. Disconnect the evaporative emission (EVAP) pipe quick connect fitting (1) from the sender. Refer to Plastic Collar Quick Connect Fitting Service .
  8. Disconnect the fuel level sensor wiring harness electrical connectors (4) from the sender.
  9. Reposition the fuel feed pipe, EVAP pipe, and harness connector out of the way.
  10. Fig 3: Identifying J 45722
    GM1755109Courtesy of GENERAL MOTORS COMPANY
  11. Install the J 45722 to the lock ring.
  12. Fig 4: Identifying Lock Ring
    GM1642096Courtesy of GENERAL MOTORS COMPANY
    CAUTION:

    Avoid damaging the lock ring. Use only J-45722 to prevent damage to the lock ring.

    CAUTION:

    Do Not handle the fuel sender assembly by the fuel pipes. The amount of leverage generated by handling the fuel pipes could damage the joints.

    NOTE:
    • The fuel sender assembly may spring up from its position.
    • When removing the fuel sender assembly from the fuel tank, be aware that the reservoir bucket is full of fuel. It must be tipped slightly during removal to avoid damage to the float. Discard the fuel sender assembly O-ring seal and replace it with a new one.
    • Carefully discard the fuel in the reservoir bucket into an approved container.
    NOTE:

    Do NOT use impact tools. Significant force will be required to release the lock ring. The use of a hammer and screwdriver is not recommended. Secure the fuel tank in order to prevent fuel tank rotation.

  13. Use the J 45722 and a long breaker-bar in order to unlock the fuel sender lock ring. Rotate the lock ring in a counterclockwise direction.
  14. Remove the J 45722 .
  15. Fig 5: Identifying Vent Line Quick Connect Fitting
    GM1755110Courtesy of GENERAL MOTORS COMPANY
  16. Raise the sender slightly from the fuel tank and disconnect the vent line quick connect fitting (1) from the sender. Refer to Plastic Collar Quick Connect Fitting Service .
  17. Remove the fuel sender lock ring.
  18. Fig 6: Identifying vapor line quick connect fittings
    GM1755111Courtesy of GENERAL MOTORS COMPANY
  19. Slowly raise the module until the vapor line quick connect fittings (1) are visible.
  20. In order to prevent the internal vent lines from dropping into the raw gasoline, tie a string to the lines and secure.
  21. Disconnect the vapor line quick connect fittings (1 and 2) from the module flange. Refer to Plastic Collar Quick Connect Fitting Service .
  22. Fig 7: View Of fuel level sensor float arm
    GM1755112Courtesy of GENERAL MOTORS COMPANY
  23. Slowly raise the sender until the fuel level sensor float arm is just visible.
  24. NOTE:

    When removing the sender from the fuel tank, be aware that the sender reservoir bucket is full of fuel. The sender must be tipped slightly during removal to avoid bending the fuel level sensor float arm.

  25. Tilt the sender toward the rear of the fuel tank to allow the level sensor float arm to clear the tank opening. Remove the sender from the tank.
  26. Carefully discard the fuel in the sender reservoir bucket into an approved fuel container.
  27. NOTE:

    DO NOT reuse the old fuel pump sender seal.

  28. Remove and discard the fuel pump sender O-ring seal.
  29. Fig 8: Checking Lock Ring For Flatness
    GM1617750Courtesy of GENERAL MOTORS COMPANY
    NOTE:
    • Some lock ring were manufactured with DO NOT REUSE stamped into them. These lock rings may be reused if they are not damaged or warped.
    • Inspect the lock ring for damage due to improper removal or installation procedures. If damage is found, install a NEW lock ring.
    • Check the lock ring for flatness.
  30. Place the lock ring on a flat surface. Measure the clearance between to lock ring and the flat surface using a feeler gauge at 7 different points.
  31. If the warpage is less than 0.41 mm (0.016 in), the lock ring does not require replacement.
  32. If the warpage is greater than 0.41 mm (0.016 in), the lock ring must be replaced.