GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

Caution: In order to reduce the risk of fire and personal injury that may result from a fuel leak, always install the fuel injector O-rings in the proper position. If the upper and lower O-rings are different colors (black and brown), be sure to install the black O-ring in the upper position and the brown O-ring in the lower position on the fuel injector. The O-rings are the same size but are made of different materials.

Notice: Cap the fittings and plug the holes when servicing the fuel system in order to prevent dirt and other contaminants from entering the open pipes and passages.

An 8-digit identification number is stamped on the fuel rail. Refer to this number if servicing or part replacement is required.


    Object Number: 1885563  Size: SH
  1. Disconnect the chassis fuel feed line quick connect fitting (2) from the fuel rail. Refer to Metal Collar Quick Connect Fitting Service.
  2. Remove the upper intake manifold. Refer to Upper Intake Manifold Replacement .

  3. Object Number: 1775159  Size: SH
  4. Disconnect the fuel injector wiring harness electrical connector from the engine coolant temperature (ECT) sensor.

  5. Object Number: 1775160  Size: SH
  6. Disconnect the fuel injector wiring harness electrical connector from the camshaft position (CMP) sensor.

  7. Object Number: 1775161  Size: SH
  8. Remove the fuel injector wiring harness electrical connector bracket bolt from the intake manifold.

  9. Object Number: 1557674  Size: SH
  10. Remove the fuel rail bolts.
  11. Remove the fuel rail (1).
  12. Remove the fuel injector O-ring seal from the spray tip end of each injector, if the fuel rail was removed for other purposes.
  13. If replacing the fuel rail proceed to the disassembly procedure, otherwise proceed to the Installation Procedure.

Disassembly Procedure


    Object Number: 1797922  Size: SH
  1. Disconnect the fuel injector wiring harness electrical connectors from the fuel injectors.
  2. Remove the fuel injector wiring harness retainers from the fuel rail.
  3. Remove the fuel injector wiring harness.

  4. Object Number: 1797926  Size: SH
  5. Remove the fuel injector retainers (1).
  6. Remove the fuel injectors (3).
  7. Remove the fuel injector upper (2) and lower (4) O-ring seals.

Assembly Procedure


    Object Number: 1797926  Size: SH
  1. Lubricate the NEW injector O-ring seals with clean engine oil.
  2. Install the NEW fuel injector upper (2) and lower (4) O-ring seals.
  3. Install the fuel injectors (3).
  4. Instal the fuel injector retainers (1).

  5. Object Number: 1797922  Size: SH
  6. Position the fuel injector wiring harness.
  7. Install the fuel injector wiring harness retainers to the fuel rail.
  8. Connect the fuel injector wiring harness electrical connectors to the fuel injectors.

Installation Procedure

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.


    Object Number: 1557674  Size: SH
  1. Install NEW fuel injector O-ring seals onto the spray tip end of each injector, if the fuel rail was removed for other purposes.
  2. Install the fuel rail (1).
  3. Notice: Refer to Fastener Notice in the Preface section.

  4. Install the fuel rail bolts.
  5. Tighten
    Tighten the bolts to 10 N·m (89 lb in).


    Object Number: 1775161  Size: SH
  6. Align the bracket pin to the hole in the lower intake manifold.
  7. Install the fuel injector wiring harness electrical connector bracket bolt to the intake manifold.
  8. Tighten
    Tighten the bolt to 14 N·m (10 lb ft).


    Object Number: 1775160  Size: SH
  9. Connect the fuel injector wiring harness electrical connector to the CMP sensor.

  10. Object Number: 1775159  Size: SH
  11. Connect the fuel injector wiring harness electrical connector to the ECT sensor.
  12. Install the upper intake manifold. Refer to Upper Intake Manifold Replacement .

  13. Object Number: 1885563  Size: SH
  14. Connect the chassis fuel feed line quick connect fitting (2) to the fuel rail. Refer to Metal Collar Quick Connect Fitting Service .
  15. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection .
  16. Inspect for leaks.
  17. 11.1. Turn ON the ignition, with the engine OFF for 10 seconds.
    11.2. Turn OFF the ignition for 10 seconds.
    11.3. Turn ON the ignition for 10 seconds.
    11.4. Inspect for fuel leaks.

Removal Procedure

Warning: In order to reduce the risk of fire and personal injury that may result from a fuel leak, always install the fuel injector O-rings in the proper position. If the upper and lower O-rings are different colors (black and brown), be sure to install the black O-ring in the upper position and the brown O-ring in the lower position on the fuel injector. The O-rings are the same size but are made of different materials.

Caution: Cap the fittings and plug the holes when servicing the fuel system in order to prevent dirt and other contaminants from entering the open pipes and passages.

An 8-digit identification number is stamped on the fuel rail. Refer to this number if servicing or part replacement is required.


    Object Number: 1885563  Size: SH
  1. Disconnect the chassis fuel feed line quick connect fitting (2) from the fuel rail. Refer to Metal Collar Quick Connect Fitting Service.
  2. Remove the upper intake manifold. Refer to Upper Intake Manifold Replacement.

  3. Object Number: 1775159  Size: SH
  4. Disconnect the fuel injector wiring harness electrical connector from the engine coolant temperature (ECT) sensor.

  5. Object Number: 1775160  Size: SH
  6. Disconnect the fuel injector wiring harness electrical connector from the camshaft position (CMP) sensor.

  7. Object Number: 1775161  Size: SH
  8. Remove the fuel injector wiring harness electrical connector bracket bolt from the intake manifold.

  9. Object Number: 1557674  Size: SH
  10. Remove the fuel rail bolts.
  11. Remove the fuel rail (1).
  12. Remove the fuel injector O-ring seal from the spray tip end of each injector, if the fuel rail was removed for other purposes.
  13. If replacing the fuel rail proceed to the disassembly procedure, otherwise proceed to the Installation Procedure.

Disassembly Procedure


    Object Number: 1797922  Size: SH
  1. Disconnect the fuel injector wiring harness electrical connectors from the fuel injectors.
  2. Remove the fuel injector wiring harness retainers from the fuel rail.
  3. Remove the fuel injector wiring harness.

  4. Object Number: 1797926  Size: SH
  5. Remove the fuel injector retainers (1).
  6. Remove the fuel injectors (3).
  7. Remove the fuel injector upper (2) and lower (4) O-ring seals.

Assembly Procedure


    Object Number: 1797926  Size: SH
  1. Lubricate the NEW injector O-ring seals with clean engine oil.
  2. Install the NEW fuel injector upper (2) and lower (4) O-ring seals.
  3. Install the fuel injectors (3).
  4. Instal the fuel injector retainers (1).

  5. Object Number: 1797922  Size: SH
  6. Position the fuel injector wiring harness.
  7. Install the fuel injector wiring harness retainers to the fuel rail.
  8. Connect the fuel injector wiring harness electrical connectors to the fuel injectors.

Installation Procedure

Caution: 

   • 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.


    Object Number: 1557674  Size: SH
  1. Install NEW fuel injector O-ring seals onto the spray tip end of each injector, if the fuel rail was removed for other purposes.
  2. Install the fuel rail (1).
  3. Caution: Refer to Fastener Caution in the Preface section.

  4. Install the fuel rail bolts.
  5. Tighten
    Tighten the bolts to 10 N·m (89 lb in).


    Object Number: 1775161  Size: SH
  6. Align the bracket pin to the hole in the lower intake manifold.
  7. Install the fuel injector wiring harness electrical connector bracket bolt to the intake manifold.
  8. Tighten
    Tighten the bolt to 14 N·m (10 lb ft).


    Object Number: 1775160  Size: SH
  9. Connect the fuel injector wiring harness electrical connector to the CMP sensor.

  10. Object Number: 1775159  Size: SH
  11. Connect the fuel injector wiring harness electrical connector to the ECT sensor.
  12. Install the upper intake manifold. Refer to Upper Intake Manifold Replacement.

  13. Object Number: 1885563  Size: SH
  14. Connect the chassis fuel feed line quick connect fitting (2) to the fuel rail. Refer to Metal Collar Quick Connect Fitting Service.
  15. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection.
  16. Inspect for leaks.
  17. 11.1. Turn ON the ignition, with the engine OFF for 10 seconds.
    11.2. Turn OFF the ignition for 10 seconds.
    11.3. Turn ON the ignition for 10 seconds.
    11.4. Inspect for fuel leaks.