GM Service Manual Online
For 1990-2009 cars only

Tools Required

    • J 34730-1A Fuel Pressure Gauge
    • J 37088-A Fuel Line Quick-Connect Separator
    • J 41081 Injector Remover

Removal Procedure

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: 166861  Size: SH
  1. Relieve the fuel system pressure. Refer to Fuel Pressure Relief .
  2. Remove the intake air duct clamp (2) from the air cleaner assembly (3).
  3. Remove the intake air duct clamp (5) from the MAF sensor (4).
  4. Remove the MAF sensor electrical connector from the MAF sensor (4).

  5. Object Number: 53639  Size: SH
  6. Remove the EGR pipe and crankcase ventilation pipe at throttle body spacer.

  7. Object Number: 18886  Size: SH
  8. Remove the brake booster vacuum hose at intake manifold.
  9. Remove the front bank spark plug wires.
  10. Remove the fuel injector harness electrical connectors from the fuel injectors.

  11. Object Number: 154854  Size: SH
  12. Remove the transaxle vent hose (2) from the clip attached to the accelerator control cable (1).

  13. Object Number: 20434  Size: SH
  14. Remove the fuel pressure regulator vacuum line from the fuel pressure regulator.

  15. Object Number: 236766  Size: SH
  16. Remove the fuel rail ground wire (1) nut at the rear cylinder head.

  17. Object Number: 239214  Size: SH
  18. Remove the quick-connect clips (4), (5) from the fuel pipes (engine side).
  19. Disconnect the fuel feed (2) and fuel return (3) quick-connect fittings at fuel rail. Refer to Metal Collar Quick Connect Fitting Service .

  20. Object Number: 18881  Size: SH
  21. Dis-connect fuel pipe bracket at the EGR valve if applicable.
  22. Remove throttle body mount bolts. Refer to Throttle Body Assembly Replacement .
  23. Remove the throttle body spacer bolts.
  24. Release locking tabs on fuel rail and pry each injector out of intake manifold using J 41081. Refer to Fuel Injector Replacement .
  25. Remove the fuel rail assembly.

Disassemble Procedure


    Object Number: 219186  Size: SH
  1. Remove the injector harness.
  2. Spread the injector retaining clip(s) (10) to release the injector(s) (12) from the fuel rail assembly.
  3. Remove the injector(s) (12) from fuel rail.
  4. Remove the upper (11) and lower (13) O-ring(s) from injector(s).
  5. Discard the O-rings.
  6. Clean the throttle body O-ring surfaces. Refer to Throttle Body Inspection and Cleaning .

Assemble Procedure


    Object Number: 219186  Size: SH
  1. Lubricate the new upper (11) and lower (13) injector O-ring(s) with clean engine oil.
  2. Install the new upper (11) and lower (13) injector O-ring(s) on the injector(s) (12).
  3. Install the injector(s) (12) to fuel rail with new retainer clip(s) (10).
  4. Ensure the injector(s) (12) are aligned by orientating the electrical connector perpendicular to the crankshaft.
  5. Install the injector harness.

Installation Procedure


    Object Number: 18881  Size: SH
  1. Install the fuel rail with injector(s) to intake manifold.
  2. A snap will be heard when the injectors are properly seated.

  3. Object Number: 19023  Size: SH
  4. Install the throttle body spacer gasket and throttle body spacer (3) to the intake manifold (4).
  5. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  6. Tighten the bolts.
  7. Tighten
    Tighten the bolts to 12 N·m (106 lb in).

  8. Install the new throttle body gasket (2), throttle body (1), and bolts.
  9. Tighten the bolts.
  10. Tighten
    Tighten the bolts to 12 N·m (106 lb in).

    Notice: Use an emery cloth in order to remove rust or burrs from the fuel pipe. Use a radial motion with the fuel pipe end in order to prevent damage to the O-ring sealing surface.

  11. Clean the quick-connect fittings.

  12. Object Number: 12784  Size: SH
  13. Apply a few drops of clean engine oil to the male ends of the engine fuel rail inlet and outlet pipes.
  14. Install the quick-connect fittings to fuel rail.

  15. Object Number: 12786  Size: SH
  16. Push both sides of fitting together to cause the retaining tabs/fingers to snap into place.

  17. Object Number: 12787  Size: SH
  18. Pull on both sides of fitting to make sure connection is secure once installed.
  19. Repeat Steps 8 through 12 for the other fitting.
  20. Install the quick-connect clips to the fuel pipes (engine side).
  21. Install the fuel pipe bracket at the EGR valve if applicable.

  22. Object Number: 20434  Size: SH
  23. Install the fuel pressure regulator and crankcase ventilation vacuum lines.

  24. Object Number: 236766  Size: SH
  25. Install the fuel rail ground wire (1) at rear cylinder head.
  26. Tighten
    Tighten the fuel rail ground wire bolt to 11 N·m (97 lb in).

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

  28. Object Number: 53639  Size: SH
  29. Install the injector harness and injector electrical connectors.
  30. Install the front bank spark plug wires.
  31. Install the brake booster vacuum hose at intake manifold vacuum fitting.
  32. Install the EGR pipe at throttle body spacer.
  33. Tighten
    Tighten the EGR pipe bolt to 28 N·m (21 lb ft).


    Object Number: 166861  Size: SH
  34. Install the MAF sensor (4) electrical connector.
  35. Install the intake air duct (1) clamp (5) from the MAF sensor (4).
  36. Install the intake air duct (1) clamp (2) from the air cleaner assembly (3).
  37. Add fuel to the tank.
  38. Tighten fuel filler cap.
  39. Install the negative battery cable.
  40. Inspect for leaks.
  41. 28.1. Turn the ignition switch ON for 2 seconds.
    28.2. Turn the ignition switch OFF for 10 seconds.
    28.3. Turn the ignition switch ON.
    28.4. Check for fuel leaks.

    Object Number: 20426  Size: SH
  42. Install the intake manifold top cover.
  43. Tighten
    Tighten the nuts to 3 N·m (27 lb in).