An eight digit identification number is located on the fuel rail assembly. Refer to this model identification number if servicing or part replacement is required.

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 .
3. Remove the upper intake manifold. Refer to Intake Manifold Replacement in Engine Mechanical.
4. Remove the distributor. Refer to Distributor Replacement in Engine Electrical.
5. Before removal, clean the fuel rail assembly with a spray type engine cleaner, GM X-30A or equivalent, if necessary. Follow the package instructions. Do not soak fuel rails in liquid cleaning solvent.

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.

6. Disconnect the fuel feed and return pipes at the fuel rail.
7. Disconnect the injector harness electrical connector.



8. Disconnect the fuel pressure regulator vacuum hose from the intake manifold fitting.



9. Remove the fuel rail stud (1) and bolts (2), (3).



10. Remove the fuel rail from the intake manifold.
11. Remove the fuel feed and return pipe O-rings and discard.
12. Remove the injector electrical harness from the fuel rail.
13. Remove the injector O-ring seal from the spray tip end of each injector. Discard the seals. With the O-ring removed, the O-ring backup may slip off of the injector. Be sure to retain O-ring backup for reuse.

1. Install the injector electrical harness on the fuel rail.
2. Lubricate the new lower injector O-ring seals with clean engine oil.

Important: Ensure that the O-ring backups are on the injectors before installing the new O-rings.

3. Install the new O-ring seals on the spray tip end of each injector.
4. Install the new fuel feed and return pipe O-ring seals.
5. Install the fuel rail assembly in the intake manifold. Tilt the rail assembly to install the injectors.




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.

6. Install the fuel rail stud (1) and bolts (2), (3).

Tighten

•	Tighten the fuel rail stud (1) to 25 N·m (18 lb ft).

•	Tighten the fuel rail bolts (2), (3) to 10 N·m (89 lb in).




7. Connect the fuel pressure regulator vacuum hose to the intake manifold fitting.
8. Connect the injector harness electrical connector.
9. Connect the fuel feed and return pipes.

Tighten
Use a backup wrench and tighten the fuel pipe fittings to 27 N·m (20 lb ft).

10. Tighten the fuel filler cap.
11. Connect the negative battery cable.
12. Inspect for leaks.

12.1.

Turn the ignition ON for 2 seconds.

12.2.

Turn the ignition OFF for 10 seconds.

12.3.

Turn the ignition ON.

12.4.

Inspect for fuel leaks.

13. Install the distributor. Refer to Distributor Replacement in Engine Electrical.
14. Install the upper intake manifold. Refer to Intake Manifold Replacement in Engine Mechanical.