GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2009 🢒 STS 🢒 Diagnostic Navigation 🢒 Vehicle Diagnostic Information 🢒 Fuel Pump Replacement

Fuel Pump Replacement LLT

Special Tools

EN-48896 HP Fuel Pump Installation Alignment Gage

Removal Procedure
  1. Relieve the low and high side fuel system pressure. Refer to Fuel Pressure Relief.
  2. Remove the cross vehicle brace. Refer to Cross Vehicle Brace Replacement.
  3. Remove the high pressure fuel pump shield. Refer to Fuel Pipe Shield Replacement.
  4. Remove the intake manifold. Refer to Intake Manifold Replacement.
  5. Remove the wiper module. Refer to Windshield Wiper Motor Replacement.

    6. Object Number: 1977751 Size: SH
  6. Disconnect the engine wiring harness electrical connector from the high pressure fuel pump.
  7. Remove the radiator surge tank outlet pipe. Refer to Radiator Surge Tank Outlet Hose/Pipe Replacement.
  8. Remove the low pressure feed pipe. Refer to Fuel Feed Pipe Replacement.
  9. Remove the high pressure pipe. Refer to Fuel Feed Intermediate Pipe Replacement. Discard this pipe.
  10. Remove and discard the high pressure fuel pump bolts (4).
  11. Remove the high pressure fuel pump (3).
  12. Remove and discard the high pressure fuel pump gasket (2).
  13. Remove and discard the high pressure fuel pump O-ring.
  14. Remove the high pressure fuel pump roller lifter.

Installation Procedure

    Note: The camshaft must be in the base circle position before the high pressure fuel pump is installed.

  1. Use the EN-48896 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 GM P/N 12345501 (Canadian P/N 992704) or equivalent.
  3. Install high pressure fuel pump roller lifter.
  4. Install a NEW high pressure fuel pump O-ring.

    5. Object Number: 1977751 Size: SH

    Note: The high pressure fuel pump gasket has a retaining feature to hold the pump retaining bolts in place.

  5. Position the NEW high pressure fuel pump gasket (2) and bolts (4) to the fuel pump.
  6. Install the high pressure fuel pump (3) to the cylinder head (1). Force will be required while hand tightening the bolts.

    7. Caution: Refer to Fastener Caution in the Preface section.

  7. Tighten the high pressure fuel pump retaining bolts.

    8. Tighten
    Tighten the fuel pump 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.
  10. Install the fuel feed pipe to the high pressure fuel pump. Refer to Fuel Feed Pipe Replacement.
  11. Connect the high pressure fuel pump wiring harness.
  12. Install the radiator surge tank outlet pipe. Refer to Radiator Surge Tank Outlet Hose/Pipe Replacement.
  13. Install the fuel tank cap.

    14. Note: If a fuel leak accrues at the fuel rail, the fuel rail will need to be replaced.

  14. Inspect for leaks using the following procedure:
    15. 14.1. Turn ON the ignition, with the engine OFF for 2 seconds.
    14.2. Turn OFF the ignition, for 10 seconds.
    14.3. Turn ON the ignition, with the engine OFF.
    14.4. Inspect for fuel leaks.
  15. Install the pressure relief cap to the fuel feed pipe.
  16. Install the wiper module. Refer to Windshield Wiper Motor Replacement.
  17. Install the intake manifold. Refer to Intake Manifold Replacement.
  18. Install the high pressure fuel pump shield. Refer to Fuel Pipe Shield Replacement.
  19. Install the cross vehicle brace. Refer to Cross Vehicle Brace Replacement.