GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

Notice: Use care in removing the fuel injectors to prevent damage to the electrical connector terminals.

The fuel injector is serviced as a complete assembly only.

Also since the injectors are electrical components, these injectors should not be immersed in any type of liquid solvent or cleaner as damage may occur. Fuel injector cleaning is not recommended.

    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.

  1. Disconnect the negative battery cable.
  2. Relieve the fuel system pressure. Refer to Fuel Pressure Relief Procedure .
  3. Remove the Upper Manifold Assembly. Refer to Upper Intake Manifold replacement in Engine Mechanical.
  4. Remove the Fuel Meter Body Assembly. Refer to Fuel Meter Body Assembly Replacement .

Disassembly Procedure


    Object Number: 331936  Size: SH
  1. Disassemble the lower hold down plate and the nuts (1).
  2. While pulling the poppet nozzle tube downward, push with a small tip punch down between the injector terminals until the injector is removed.

Assembly Procedure

Important: Each injector is calibrated for a specific flow rate. Order the correct injector for the application being serviced when replacing the fuel injectors.


    Object Number: 331936  Size: SH
  1. Lubricate the new injector O-ring seals with clean engine oil (2).
  2. Install the O-rings on the injector assembly (2).
  3. Assemble the Central SFI fuel injector assembly into the fuel meter body injector socket.
  4. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  5. Assemble the lower hold down plate and nuts (1).
  6. Tighten
    Tighten the nuts to 3.0 N·m (27 lb in).

Installation Procedure

  1. Install the fuel meter body assembly. Refer to Fuel Meter Body Assembly Replacement .
  2. Install the upper manifold assembly. Refer to Engine Mechanical.
  3. Connect the negative battery cable.
  4. Turn the ignition On for 2 seconds.
  5. Turn the ignition Off for 2 seconds.
  6. Turn the ignition On for 2 seconds.
  7. Inspect for fuel leaks.