GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2004 🢒 CTS 🢒 Engine 🢒 Engine Mechanical - 2.6L and 3.2L 🢒 Fuel Injector and Fuel Rail Replacement

Removal Procedure

    Caution: Refer to Gasoline/Gasoline Vapors Caution in the Preface section.

  1. Relieve the fuel system pressure. Refer to Fuel Pressure Relief .
  2. Remove the intake plenum. Refer to Intake Plenum Replacement in Engine Mechanical-2.6L and 3.2L.

    3. Object Number: 785815 Size: MH
  3. Refer to Metal Collar Quick Connect Fitting Service in order to disconnect the following quick connect fittings from the fuel rail:
    4. • The return hose/pipe (1)
    • The feed hose/pipe (2)

    Object Number: 818890 Size: SH
  4. Remove the fuel rail brace bolt from the intake manifold.
  5. Disconnect the fuel injector electrical connectors from each fuel injector.
  6. Unclip the harness from the fuel rail and position aside.
  7. Disconnect the atmospheric vent hose from the fuel pressure regulator.

    8. Object Number: 818891 Size: SH
  8. Remove the bolts securing the fuel rail to the intake manifold.

    9. Caution: Wear safety glasses when using compressed air in order to prevent eye injury.

  9. Use compressed air in order to blow dirt out of the area where the injectors enter the intake casting.

    10. 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.


    Object Number: 818892 Size: SH
  10. Carefully lift the fuel rail assembly from the intake manifold.
  11. Remove the retainers from the fuel injectors.
  12. Remove the fuel injectors from the fuel rail.
  13. Remove the O-ring seals from the fuel injectors. Discard the O-ring seals.

Installation Procedure

    Notice: 

       • Use care when servicing the fuel system components, especially the fuel injector electrical connectors, the fuel injector tips, and the injector O-rings. Plug the inlet and the outlet ports of the fuel rail in order to prevent contamination.
       • Do not use compressed air to clean the fuel rail assembly as this may damage the fuel rail components.
       • Do not immerse the fuel rail assembly in a solvent bath in order to prevent damage to the fuel rail assembly.

  1. Lubricate the new fuel injector O-ring seals with clean engine oil.
  2. Install the new fuel injector O-ring seals on to the fuel injectors.
  3. Install the fuel injectors to the fuel rail with the new retainer clips.
  4. Ensure that the injectors are aligned by orienting the electrical connectors perpendicular to the crankshaft centerline.

    5. Object Number: 818892 Size: SH
  5. Align the fuel injectors and fuel rail to the intake manifold.
  6. Carefully press the fuel rail assembly downward until fully seated against the intake manifold.
  7. Install the fuel rail with the injectors to the intake manifold.

    8. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 818891 Size: SH
  8. Install the bolts securing the fuel rail to the intake manifold.

    9. Tighten
    Tighten the fuel rail bolts to 8 N·m (71 lb in).

  9. Connect the atmospheric vent hose to the fuel pressure regulator.
  10. Clip the fuel injector electrical harness to the fuel rail.
  11. Connect the fuel injector electrical connectors to each fuel injector.

    12. Object Number: 818890 Size: SH
  12. Install the fuel rail brace bolt to the intake manifold.

    13. Tighten
    Tighten the fuel rail brace bolt to 8 N·m (71 lb in).


    Object Number: 785815 Size: MH
  13. Refer to Metal Collar Quick Connect Fitting Service in order to connect the following quick connect fittings to the fuel rail:
    14. • The feed hose/pipe (2)
    • The return hose/pipe (1)
  14. Install the intake plenum. Refer to Intake Plenum Replacement in Engine Mechanical-2.6L and 3.2L.