GM Service Manual Online
For 1990-2009 cars only

Special Tools

    • EN-48279 Primary Fuel Pump Locking Ring Remover/Installer
    • EN-48278 Secondary Fuel Pump Locking Ring Remover/Installer

Removal Procedure


    Object Number: 1760006  Size: SH

    Warning: Remove 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.
  2. Warning: Refer to Battery Disconnect Warning in the Preface section.

  3. Disconnect the negative battery cable.
  4. Fold the rear seat.
  5. Lift up the carpet and the insulation.
  6. Remove the primary and secondary fuel pump access covers.

  7. Object Number: 1760008  Size: SH
  8. Disconnect the electrical connector at the secondary fuel pump assembly.

  9. Object Number: 1785005  Size: SH
  10. Install the EN-48278 to the secondary fuel pump and turn it counterclockwise.
  11. Remove the secondary fuel pump lock ring.
  12. Note: Be careful not to damage the fuel sender for the correct fuel leveling while removing the fuel pump assembly from the fuel tank.

    Note: O-ring should not be contaminated by fuel.

  13. Remove the secondary fuel pump assembly and the O-ring from the fuel tank.

  14. Object Number: 1760009  Size: SH
  15. Disconnect the primary fuel pump-to-secondary fuel pump connecting hose at the secondary fuel pump.

  16. Object Number: 1760011  Size: SH
  17. Disconnect the electrical connector at the primary fuel pump assembly.
  18. Disconnect the fuel feed line.

  19. Object Number: 1785018  Size: SH
  20. Install EN-48278 to the primary fuel pump and turn it counterclockwise.
  21. Remove the primary fuel pump lock ring.
  22. Note: Be careful not to damage the fuel sender for the correct fuel leveling while removing the fuel pump assembly from the fuel tank.

    Note: O-ring should not be contaminated by fuel.

  23. Remove the primary fuel pump assembly and the O-ring from the fuel tank.

Installation Procedure


    Object Number: 1760013  Size: SH
  1. Clean all of the mating surface on the both fuel pump and fuel tank.
  2. Note: Do not reuse the primary fuel pump O-ring.

    Note: For ease of the primary fuel pump-to-secondary fuel pump connecting hose, install the primary fuel pump assembly first. Be sure that the arrow on the primary fuel pump assembly should be aligned with the arrow on the fuel tank.

  3. Position the new primary fuel pump O-ring and the primary fuel pump first into the fuel tank in the same location as removed.

  4. Object Number: 1760009  Size: SH
  5. Pull the primary fuel pump-to-secondary fuel pump connecting hose towards the secondary fuel pump assembly.
  6. Connect the primary fuel pump-to-secondary fuel pump connecting hose at the secondary fuel pump.

  7. Object Number: 1760018  Size: SH

    Note: Do not reuse the secondary fuel pump O-ring.

    Note: Be sure that the arrow on the secondary fuel pump assembly should be aligned with the arrow on the fuel tank.

  8. Position the new secondary fuel pump O-ring and the secondary fuel pump into the fuel tank in the same location as removed.

  9. Object Number: 1760008  Size: SH
  10. Install the secondary fuel pump lock ring by turning EN-48278 clockwise.
  11. Connect the electrical connector at the secondary fuel pump.

  12. Object Number: 1760011  Size: SH
  13. Install the primary fuel pump lock ring by turning EN-48279 clockwise.
  14. Connect the electrical connector at the primary fuel pump.
  15. Connect the fuel feed line.

  16. Object Number: 1760006  Size: SH
  17. Install the primary and secondary fuel pump access covers.
  18. Connect the negative battery cable.
  19. Perform an operational check of the fuel pump.
  20. Fold the rear seat back to the original position.