GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

    Caution: Refer to Relieving Fuel Pressure Caution in the Preface section.


    Object Number: 1263846  Size: SH
  1. Relieve the fuel system pressure. Refer to Fuel Pressure Relief .
  2. Caution: Refer to Battery Disconnect Caution in the Preface section.

  3. Disconnect the negative battery cable.
  4. Remove the spark plug cover.
  5. Disconnect the fuel injector harness connectors.
  6. Remove the fuel pressure regulator vacuum hose.

  7. Object Number: 1263847  Size: SH
  8. Remove the fuel feed line.
  9. Remove the fuel rail mounting bolts.
  10. 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.

    Important: If an injector becomes separated from the rail and remains in the cylinder head, replace the injector O-ring seals and the retaining clip.

  11. Remove the fuel rail with the fuel injectors attached.

  12. Object Number: 1263849  Size: SH
  13. Remove the fuel pressure regulator. Refer to Fuel Pressure Regulator Replacement .
  14. Remove the fuel injector retainer clips.
  15. Remove the fuel injectors by pulling down and out.
  16. Discard the fuel injector O-rings.

Installation Procedure


    Object Number: 1263849  Size: SH

    Important: Different injectors are calibrated for different flow rates. When ordering new fuel injectors, be certain to order the identical part number that is inscribed on the old injector.

  1. Lubricate the new fuel injector O-rings with engine oil. Install the new O-rings on the fuel injectors.
  2. Install the fuel injectors into the fuel rail sockets with the fuel injector terminals facing outward.

  3. Object Number: 1263848  Size: SH
  4. Install the fuel injector retainer clips onto the fuel injectors and the fuel rail ledge.
  5. Make sure that the clip is parallel to the fuel injector harness connector.
  6. Install the fuel pressure regulator. Refer to Fuel Pressure Regulator Replacement .
  7. Install the fuel rail assembly into the cylinder head.
  8. Notice: Refer to Fastener Notice in the Preface section.

  9. Install the fuel rail mounting bolts.
  10. Tighten
    Tighten the fuel rail mounting bolts to 25 N·m (18 lb ft).


    Object Number: 1263847  Size: SH
  11. Connect the fuel feed line.

  12. Object Number: 1263846  Size: SH
  13. Install the fuel pressure vacuum hose.
  14. Connect the fuel injector harness connectors. Rotate each fuel injector as required to avoid stretching the wiring harness.
  15. Install the spark plug cover.
  16. Install the intake manifold bracket with the bolts.
  17. Connect the negative battery cable.
  18. Perform a leak check of the fuel rail and fuel injectors.