GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 1998 🢒 Firebird 🢒 Engine 🢒 Engine Controls - 3.8L 🢒 Fuel Injector Replacement

Removal Procedure

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.

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: 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. Always maintain cleanliness when servicing fuel system components.


    Object Number: 12687 Size: SH
  1. Remove the fuel rail. Refer to Fuel Injection Fuel Rail Assembly Replacement .
  2. Remove the fuel injector retaining clip (2).
  3. Remove the fuel injector (3).
  4. Remove the fuel injector upper O-ring (1).
  5. Remove the fuel injector lower O-ring (5).
  6. Remove the fuel injector O-ring back up (4).

Installation Procedure

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. Coat all new O-rings with clean engine oil before installing.
  2. Install the fuel injector O-ring back up (4).
  3. Install the fuel injector lower O-ring (5).
  4. Install the fuel injector upper O-ring (1).
  5. Install the fuel injector (3).
  6. Install the fuel injector retaining clip (2).
  7. Reinstall the fuel rail. Refer to Fuel Injection Fuel Rail Assembly Replacement .

    8. 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.

  8. Reconnect the negative battery cable.
  9. Inspect for leaks.
    10. 9.1. Turn the ignition switch ON for 2 seconds.
    9.2. Turn the ignition switch OFF for 10 seconds.
    9.3. Turn the ignition switch ON.
    9.4. Check for fuel leaks.