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

For equivalent regional tools, refer to Special Tools


    Object Number: 2146358  Size: SH
  1. Unplug the electrical connections from the fuel injectors (1).
  2. Remove the injectors from the fuel rail.

  3. Object Number: 2184909  Size: SH
  4. Remove and discard the fuel injector hold-down clamp (3).
  5. Remove and discard the fuel injector O-ring (2) and plastic spacer (1).

  6. Object Number: 2146359  Size: SH
  7. Remove and discard the fuel injector seal (1).

  8. Object Number: 2146360  Size: SH

    Note: Do not soak or submerge the fuel rail or injectors in solvent.

  9. Clean the exterior of the fuel rail (2) and injectors in solvent.
  10. Caution: Refer to Fastener Caution in the Preface section.

  11. Inspect the high pressure fuel sensor (1) for damage.
  12. 7.1. If replacing, dry the fuel pressure sensor bore in the fuel rail with a lint free cloth.
    7.2. The bore should be free of fuel, debris, and burrs.
    7.3. Lubricate the fuel pressure sensor bore, in the fuel rail, with clean engine oil.
    7.4. Lubricate the threads and sealing area on the fuel pressure sensor with clean engine oil.
    7.5.  Install the new fuel pressure sensor hand tight.
    7.6. Remove the fuel pressure sensor and re-lubricate the bore, threads, and sealing area.
    7.7. Re-install the fuel pressure sensor and tighten to 33 N·m (25 lb ft).
  13. Clean the injector bore using the EN-47909 kit .
  14. Inspect the fuel rail and components for the following conditions:
  15. • Damage, debris, or restrictions to the fuel rail
    • Damage, debris, or restrictions to the fuel ports in the fuel rail
    • Damage to the mounting area for the fuel rail
    • Damage to the fuel rail mounting bolts
    • Damage to the threads on the fuel rail fuel feed fitting

    Object Number: 1770163  Size: SH
  16. Inspect the fuel injectors for the following conditions:
  17. • Damage to the fuel injector connector (6)
    • Damage to the fuel injector harness connector
    • Damage to the plastic fuel injector spacer (3)
    • Damage to the fuel injector tip (1)
    • Damage to the tolerance ring (2)
  18. Replace the fuel rail or injector if any damage is found. Do not attempt to repair a fuel rail or injector.
  19. Lubricate the NEW O-ring (4) with 5W30 engine oil.
  20. Install a NEW O-ring and plastic spacer on the injector. The plastic spacer has a top (5) and a bottom. The top, O-ring sealing area, is wider.

  21. Object Number: 1770169  Size: SH

    Note: Do not use any type of lubricant when installing the NEW seal (1) on the fuel injector tip.

  22. Install EN-48266 installer  (2) onto the fuel injector tip. Install a NEW seal (1) over EN-48266 installer on the injector. The seal must be installed/slid into the recessed area (3) of the fuel injector. Compress the seal with your fingers before resizing the seal using the EN-48266 sizer .
  23. Using the EN-48266 sizer  (4), resize the seal.

  24. Object Number: 2184913  Size: SH
  25. Install a NEW fuel injector hold-down clamp (2).
  26. Install the injector (1) into the fuel rail.
  27. Connect the electrical connection to the fuel rail.