GM Service Manual Online
For 1990-2009 cars only

Special Tools

    • EN-47909 Injector Bore and Sleeve Cleaning Kit
    • EN-48266 Injector Seal Installer and Sizer
    • J 2619-01 Slide Hammer
    • J-37281-A Injector Remover

Removal Procedure


    Object Number: 2035304  Size: SH
  1. Disconnect the engine wiring harness electrical connector (1) from the fuel injector wiring harness electrical connector.
  2. Remove the intake manifold assembly. Refer to Intake Manifold Replacement .

  3. Object Number: 1769947  Size: SH
  4. Remove the fuel injector insulator.

  5. Object Number: 2035275  Size: SH
  6. Relieve the high side fuel system pressure. Refer to Fuel Pressure Relief .
  7. Disconnect the engine wiring harness electrical connector (1) from the high pressure fuel pump.
  8. Remove the engine wiring harness clip (3) from the high pressure fuel pump cover.
  9. Remove the fuel feed intermediate pipe. Refer to Fuel Feed Intermediate Pipe Replacement .

  10. Object Number: 1829953  Size: SH
  11. Disconnect the fuel injector wiring harness electrical connectors from the fuel injectors.
  12. Remove the fuel rail bolts (1).
  13. Important: Carefully remove the fuel rail. The fuel injectors may come out of the cylinder head with the fuel rail.

  14. Carefully remove the fuel rail (2).

  15. Object Number: 1829978  Size: SH
  16. Remove and discard the direct fuel injector hold down clamps.

  17. Object Number: 1830014  Size: SH
  18. Remove the direct fuel injectors.

  19. Object Number: 1769952  Size: SH
  20. If necessary, use the J 2619-01 and the J-37281-A in order to remove the direct fuel injector(s).

  21. Object Number: 1829979  Size: SH
  22. Remove and discard the upper O-ring seal (1) and plastic spacer (2) from the injector(s).
  23. Carefully remove and discard the lower nylon seal (4) from the injector(s).

Installation Procedure


    Object Number: 1829979  Size: SH
  1. Install a NEW plastic spacer (2) onto the fuel injector(s).
  2. Lubricate a NEW O-ring seal (1) with silicon free engine oil GM P/N 12345610 (Canadian P/N 993193) or equivalent.
  3. Install the NEW O-ring seal (1) onto the fuel injector(s).

  4. Object Number: 1829992  Size: SH
  5. From the EN-48266 , position the EN 48266-1 to the injector tip.

  6. Object Number: 1829994  Size: SH

    Important: DO NOT lubricate the NEW seal.

  7. Install a NEW seal onto the EN 48266-1.

  8. Object Number: 1829993  Size: SH
  9. Pull the NEW seal by hand over the EN 48266-1 and into the groove in the injector.
  10. Remove the EN 48266-1 from the injector tip.

  11. Object Number: 1829997  Size: SH
  12. From the EN-48266 , install the EN 48266-2 to the injector tip.

  13. Object Number: 1829998  Size: SH
  14. Using the EN 48266-2, re-size the seal. Install the EN 48266-2, until it bottoms out against the injector body, and rotate the EN 48266-2 while applying only moderate force 180 degrees in one direction and then 180 degrees back in the other direction.
  15. Remove the EN 48266-2.

  16. Object Number: 1830014  Size: SH
  17. Install the direct fuel injectors to the cylinder head.

  18. Object Number: 1829978  Size: SH
  19. Install the NEW direct fuel injector hold down clamps.

  20. Object Number: 1829953  Size: SH
  21. Place the fuel rail (2) into position.
  22. Install the 2 outer fuel rail bolts (1) first, hand tight and install the remaining 2 bolts, hand tight.
  23. Connect the fuel injector wiring harness electrical connectors to the fuel injectors.
  24. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1769965  Size: SH
  25. Tighten the fuel rail bolts in the sequence shown.
  26. Tighten

        • Tighten the bolts a first pass to 22 N·m (16 lb ft).
        • Tighten the bolts a final pass to 22 N·m (16 lb ft).
  27. Install the fuel feed intermediate pipe. Refer to Fuel Feed Intermediate Pipe Replacement .

  28. Object Number: 2035275  Size: SH
  29. Connect the engine wiring harness electrical connector (1) to the high pressure fuel pump.
  30. Install the engine wiring harness clip (3) to the high pressure fuel pump cover.

  31. Object Number: 1769947  Size: SH
  32. Install the fuel injector insulator.

  33. Object Number: 2035304  Size: SH
  34. Connect the engine wiring harness electrical connector (1) to the fuel injector wiring harness electrical connector.
  35. Inspect for leaks using the following procedure:
  36. 22.1. Turn ON the ignition, with the engine OFF for 2 seconds.
    22.2. Turn OFF the ignition, for 10 seconds.
    22.3. Turn ON the ignition, with the engine OFF.
    22.4. Inspect for fuel leaks.
  37. Install the low side fuel pressure service port cap.
  38. Tighten the fuel fill cap.
  39. Install the intake manifold assembly. Refer to Intake Manifold Replacement .