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: 537311  Size: SH
  1. Relieve fuel system pressure. Refer to Fuel Pressure Relief .
  2. Remove the fuel rail. Refer to Fuel Injection Fuel Rail Assembly Replacement .
  3. Remove the fuel injector retaining clips (1).
  4. Remove the fuel injectors (3) from the fuel rail.
  5. Remove the fuel injector Upper O-ring (2).
  6. Remove the fuel injector lower O-ring (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 Install 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: 537311  Size: SH
  1. Install the fuel injector upper O-ring (2).
  2. Install the fuel injector lower O-ring (4).
  3. Install the fuel injector (3) to the fuel rail.
  4. Install the fuel injector retaining clips (1).
  5. Install the fuel rail. Refer to Fuel Injection Fuel Rail Assembly Replacement .
  6. 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.

  7. Connect the negative battery cable.
  8. Inspect for fuel leaks using the following procedure:
  9. 7.1. Turn ON the ignition, for 2 seconds.
    7.2. Turn OFF the ignition, for 10 seconds.
    7.3. Turn ON the ignition.
    7.4. Inspect for fuel leaks.