GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

  1. Relieve the fuel system pressure. Refer to Fuel Pressure Relief .

  2. Object Number: 1560094  Size: SH
  3. Disengage the fuel feed quick connect locking clip (1).
  4. Disconnect the fuel feed line from the fuel rail. Refer to Metal Collar Quick Connect Fitting Service .

  5. Object Number: 1352026  Size: SH
  6. Refer to Plastic Collar Quick Connect Fitting Service in order to disconnect the evaporative emission (EVAP) purge hose (1) from the following:
  7. • The throttle control module (2)
    • The EVAP canister purge solenoid valve (3)
  8. Remove the intake manifold. Refer to Intake Manifold Replacement in Engine Mechanical - 3.5L (L52).

  9. Object Number: 1350694  Size: SH
  10. Disconnect the fuel injector harness connector (2) from the engine wiring harness electrical connector.
  11. Before removal, clean the fuel rail assembly and the cylinder head with a spray type engine cleaner, GM X-30A or equivalent, if necessary. Follow the package instructions. Do not soak the fuel rail in liquid cleaning solvent.

  12. Object Number: 1565309  Size: SH
  13. Remove the fuel rail bolts.
  14. Notice: 

       • Remove the fuel rail assembly carefully in order to prevent damage to the injector electrical connector terminals and the injector spray tips. Support the fuel rail after the fuel rail is removed in order to avoid damaging the fuel rail components.
       • Cap the fittings and plug the holes when servicing the fuel system in order to prevent dirt and other contaminants from entering open pipes and passages.

  15. Remove the fuel rail from the cylinder head.

  16. Object Number: 351185  Size: SH
  17. Remove the fuel injector lower O-ring seal (4) from the spray tip end of each fuel injector (3).
  18. Discard the O-ring seal (4).

  19. If the fuel rail is not being replaced, proceed to the installation procedure.

Disassembly Procedure


    Object Number: 1565311  Size: SH
  1. Remove the fuel injectors. Refer to Fuel Injector Replacement .
  2. Remove the fuel injector harness from the fuel rail.

Assembly Procedure


    Object Number: 1565311  Size: SH
  1. Install the fuel injector harness to the fuel rail.
  2. Install the fuel injectors. Refer to Fuel Injector Replacement .

Installation Procedure


    Object Number: 351185  Size: SH
  1. Lightly lubricate the new lower fuel injector O-ring seals (4) with mineral oil GM P/N 9981704.
  2. Install the NEW O-ring seals (4) on the spray tip end of each fuel injector (3).

  3. Object Number: 1565309  Size: SH
  4. Position the fuel rail to the cylinder head, inserting the spray tip ends of the fuel injectors.
  5. Notice: Refer to Fastener Notice in the Preface section.

  6. Install the fuel rail bolts.
  7. Tighten
    Tighten the bolts to 10 N·m (89 lb in).


    Object Number: 1350694  Size: SH
  8. Connect the fuel injector harness connector (2) to the engine wiring harness electrical connector.
  9. Install the intake manifold. Refer to Intake Manifold Replacement in Engine Mechanical - 3.5L (L52).

  10. Object Number: 1352026  Size: SH
  11. Refer to Plastic Collar Quick Connect Fitting Service in order to connect the EVAP purge hose (1) to the following:
  12. • The throttle control module (2)
    • The EVAP canister purge solenoid valve (3)

    Object Number: 1560094  Size: SH
  13. Connect the fuel feed line to the fuel rail. Refer to Metal Collar Quick Connect Fitting Service .
  14. Engage the fuel feed quick connect locking clip (1).
  15. Inspect for leaks.
  16. 10.1. Turn ON the ignition, with the engine OFF for 2 seconds.
    10.2. Turn OFF the ignition for 10 seconds.
    10.3. Turn ON the ignition, with the engine OFF.
    10.4. Inspect for fuel leaks.