GM Service Manual Online
For 1990-2009 cars only

Tools Required

    • J 37088-A Fuel Line Disconnect Set
    • J 44095 Fuel Pressure Adapter Fitting
    • SA9127E Gage Bar Set

Removal Procedure

    Caution: Do not allow smoking or the use of open flames in the area where work on the fuel or EVAP system is taking place. Anytime work is being done on the fuel system, disconnect the negative battery cable, except for those tests where battery voltage is required.

  1. Disconnect the negative battery cable.
  2. Loosen the clamp at the air cleaner and throttle body assembly.
  3. Remove the attachment bolts from the outlet resonator/duct assembly.
  4. Remove the outlet resonator/duct assembly.

  5. Object Number: 963185  Size: SH
  6. Remove the outlet resonator/duct assembly bracket from the manifold.

  7. Object Number: 952269  Size: SH

    Caution: Whenever fuel line fittings are loosened or disconnected, wrap a shop cloth around the fitting to collect fuel. Place the cloth in an approved container.

  8. Relieve the fuel system pressure. Refer to Fuel Pressure Relief .
  9. Disconnect the SA9127E or equivalent and the J 44095 after the pressure has been relieved.
  10. Disconnect the fuel transfer line at quick connect from the fuel line using the J 37088-A or equivalent.

  11. Object Number: 959177  Size: SH

    Notice: To avoid thread damage, only use hand tools when working with the intake manifold. Do not over tighten the bolts on the manifold.

  12. Lift and support the intake manifold assembly. Refer to Intake Manifold Replacement .

  13. Object Number: 952284  Size: SH
  14. Disconnect the electrical connectors at the fuel injectors.
  15. Remove the fuel rail line bracket bolt.
  16. Position the intake manifold onto the cylinder head.

  17. Object Number: 952255  Size: SH
  18. Disconnect the fuel rail bracket bolt at the rear of the camshaft cover.
  19. Important: Support the fuel rail lines with an open-end wrench while loosening the transfer line fittings.

  20. Loosen the transfer line fittings.
  21. Remove the fuel rail attachment bolts to manifold.

  22. Object Number: 952277  Size: SH
  23. Remove the front fuel rail assembly with the injector from the intake manifold by lifting upward.

  24. Object Number: 952262  Size: SH
  25. Remove the rear curved fuel rail assembly with injectors from the intake manifold by lifting upward.

  26. Object Number: 952218  Size: SH

    Notice: When cleaning or servicing the fuel rail, care must be taken to assure that the plastic fuel rail surfaces that mate to the injector O-rings are not scratched.

    Important: Whenever the fuel injector is removed from the fuel rail, upper and lower O-ring seals must be replaced.

    Important: If the fuel rail is being replaced, remove all of the injectors and replace all O-rings, otherwise each injector can be removed individually.

  27. Remove the fuel injector retaining clips.
  28. Remove the fuel injectors from the fuel rail.
  29. Remove and discard all injector O-ring seals by using a small pick.

Installation Procedure


    Object Number: 952218  Size: SH
  1. Install new upper and lower O-ring seals to injectors.
  2. Install the clip to the injector, aligning the tab on the injector to the notch in the clip.
  3. Important: The injector is fully seated when the tabs are aligned and the clip is engaged on the fuel rail. An audible click should be heard upon engagement. Verify the fuel rail port is engaged on each side of the clip.

  4. Align the notch in the clip to the tab on the fuel rail, and install the injector with the clip assembly to fuel rail assembly.
  5. Verify the injector is fully seated.

  6. Object Number: 952262  Size: SH

    Important: The rear curved fuel injector rail must be installed before the front rail assembly.

  7. Install the rear curved fuel injector assembly into position. Lightly press on the fuel rail to seat the fuel injectors into the injector ports.

  8. Object Number: 952277  Size: SH
  9. Install the front fuel injector assembly into position. Lightly press on the fuel rail to seat the fuel injectors onto the injector ports.
  10. Install the fuel rail to manifold bolts.
  11. Tighten
    Tighten the fuel rail-to-manifold bolts L81 to 7.5 N·m (66 lb in).

    Important: Support the fuel rail lines with an open-end wrench while tightening the transfer line fittings.

  12. Connect the fuel line quick connects.
  13. Tighten
    Tighten the transfer line fitting-to-fuel rail L81 to 15 N·m (11 lb ft).


    Object Number: 952252  Size: SH
  14. Connect the fuel rail bracket bolt at the rear of the intake manifold.
  15. Tighten
    Tighten the fuel line bracket bolt L81 to 4.4 N·m (39 lb in).


    Object Number: 964307  Size: SH
  16. Verify the gasket is positioned properly on the vacuum chamber.
  17. Install the vacuum chamber to intake manifold.

  18. Object Number: 964479  Size: SH
  19. Apply LOCTITE® 242 P/N 21485277 to the chamber bolts and tighten in sequence.
  20. Tighten
    Tighten the vacuum chamber-to-intake manifold bolts L81 to 2.5 N·m (22 lb in).

  21. Install the vacuum line to vacuum chamber port.

  22. Object Number: 959273  Size: SH
  23. Install the sleeve seals to the intake manifold top cover.

  24. Object Number: 964466  Size: SH
  25. Install the top cover into position. Apply LOCTITE® 242 and tighten the outer intake manifold bolts.
  26. Tighten
    Tighten the intake manifold top cover to manifold bolts L81 to 4.5 N·m (35 lb in).


    Object Number: 964451  Size: SH
  27. Apply LOCTITE® 242 to the 6 inner manifold cover bolts.
  28. Tighten
    Tighten the intake manifold cover to manifold bolts to 4.4 N·m (39 lb in).


    Object Number: 952284  Size: SH
  29. Raise the intake manifold up and connect the electrical connectors to fuel injectors.
  30. Attach the fuel line bracket to manifold.
  31. Tighten
    Tighten the fuel line bracket-to-manifold bolts to 6 N·m (47 lb in).


    Object Number: 959544  Size: SH
  32. Install the intake manifold assembly. Refer to Intake Manifold Replacement .

  33. Object Number: 963185  Size: SH
  34. Install the outlet resonator/duct assembly bracket to intake manifold.
  35. Tighten
    Tighten the outlet resonator/duct assembly bracket-to-intake manifold nuts L81 to 5 N·m (44 lb in).


    Object Number: 963963  Size: SH
  36. Install the outlet resonator/duct assembly into position.
  37. Tighten the clamp at throttle body assembly.
  38. Position the outlet resonator/duct assembly to support bracket and install the bolts.
  39. Tighten
    Tighten the outlet resonator/duct assembly-to-support bracket bolts L81 to 10 N·m (89 lb in).

  40. Tighten the clamp at the air cleaner assembly.
  41. Connect the negative battery cable.
  42. Tighten
    Tighten the battery terminal bolts to 17 N·m (13 lb ft).