GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

Caution: Gasoline or gasoline vapors are highly flammable. A fire could occur if an ignition source is present. Never drain or store gasoline or diesel fuel in an open container, due to the possibility of fire or explosion. Have a dry chemical (Class B) fire extinguisher nearby.

Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

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.

  1. Disconnect the negative battery cable.
  2. Relieve the fuel system pressure. Refer to Fuel Pressure Relief .
  3. Important: Mask the intake ducts. Entry of foreign objects can cause severe engine damage.

  4. Remove the intake plenum. Refer to Intake Plenum Replacement and Installation .
  5. Loosen the fuel rail bracket bolts near the fuel supply-return lines.
  6. Disconnect the fuel rail intermediate lines (supply-return). Then, position the fuel rail intermediate lines away from the fuel rail .
  7. Disconnect the fuel injector electrical connectors. Unclip the harness from the fuel rail.
  8. Disconnect the fuel rail attaching bolts from the intake manifold.
  9. Disconnect the fuel pressure regulator vacuum line.
  10. Caution: Wear safety glasses when using compressed air in order to prevent eye injury.

  11. Use compressed air in order to blow dirt out of the area where the injectors enter the intake casting.
  12. Release the locking tabs on the fuel rail. Pry each injector out of the intake manifold.
  13. Remove the fuel rail assembly.
  14. Remove the injectors from the fuel rail.
  15. Notice: If necessary, remove rust or burrs from the fuel pipes with an emery cloth. Use a radial motion with the fuel pipe end in order to prevent damage to the O-ring sealing surface. Use a clean shop towel in order to wipe off the male tube ends. Inspect all the connections for dirt and burrs. Clean or replace the components and assemblies as required.

  16. Remove the O-rings from the injectors. Discard the O-rings.

Installation Procedure

  1. Lubricate the new injector O-rings with clean engine oil.
  2. Install the new injector O-rings on the injectors.
  3. Install the injectors to the fuel rail with the new retainer clips.
  4. Ensure that the injectors are aligned by orienting the electrical connector perpendicular to the crankshaft centerline.
  5. Install the fuel rail with the injectors to the intake manifold.
  6. Reconnect the fuel pressure regulator vacuum line.
  7. Reconnect the fuel rail attaching bolts to the intake manifold.
  8. Reconnect the fuel injector electrical connectors and the clip harness to the fuel rail.
  9. Reconnect the fuel rail intermediate lines (supply-return) to the fuel rail .
  10. Tighten the fuel fittings to the fuel rail
  11. Install/tighten the fuel rail bracket bolts near the fuel supply-return lines.
  12. Reinstall the intake plenum. Refer to Intake Plenum Replacement and Installation .
  13. Connect the negative battery cable.
  14. Crank the engine for a few seconds. Turn off the engine if the engine starts.
  15. Check for fuel leaks.