GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

Notice: Use care in removing the fuel injectors in order to prevent damage to the fuel injector electrical connector pins or the fuel injector nozzles. Do not immerse the fuel injector in any type of cleaner. The fuel injector is an electrical component and may be damaged by this cleaning method.

Important: Important the fuel injector is serviced as a complete assembly only. If the fuel injectors are found to be leaking, the engine oil may be contaminated with fuel.


    Object Number: 12687  Size: SH
  1. Relieve fuel system pressure. Refer to Fuel Pressure Relief .
  2. Remove the upper intake manifold. Refer to Intake Manifold Removal .
  3. Remove the fuel rail. Refer to Fuel Injection Fuel Rail Assembly Replacement .
  4. Remove the fuel injector retaining clips (2).
  5. Remove the fuel injectors (3).
  6. Remove the fuel injector Upper O-ring (1).
  7. Remove the fuel injector lower O-ring (5).
  8. Remove the fuel injector lower O-ring Backup (4).

Installation Procedure

Important: Important each fuel injector is calibrated for a specific flow rate. Be sure to use the correct part number when ordering replacement fuel injectors. When replacing the fuel injector O-rings, be sure to install the brown O-ring in the lower position. The fuel injector lower O-ring uses a nylon collar, called the O-ring backup, to properly position the O-ring on the fuel injector. Be sure to reinstall the O-ring backup, or the sealing O-ring may move on the fuel injector when installing the fuel rail. If the sealing O-ring is not seated properly, a vacuum leak is possible and driveability complaints may occur.


    Object Number: 12687  Size: SH
  1. Install the fuel injector Upper O-ring (1).
  2. Install the fuel injector lower O-ring Backup (4).
  3. Install the fuel injector lower O-ring (5).
  4. Connect the fuel injector (3) to fuel rail.
  5. Install the fuel injector retaining clips (2).
  6. Reinstall the fuel rail. Refer to Fuel Injection Fuel Rail Assembly Replacement .
  7. Reinstall the upper intake manifold. Refer to Intake Manifold Installation .
  8. Tighten the fuel filler cap.
  9. Reconnect negative battery cable. Refer to Battery Replacement in engine electrical.
  10. Inspect for fuel leaks.
  11. 10.1. Turn the ignition switch ON for 2 seconds.
    10.2. Turn the ignition switch OFF for 10 seconds.
    10.3. Turn the ignition switch ON.
    10.4. Check for fuel leaks.