Fuel Rail: Service and Repair

Fuel Rail Assembly Model R630 - Exploded View:

Fuel Rail Assembly:

WARNING: To reduce the risk of fire and personal injury:
^ Disconnect the negative battery terminal before servicing the fuel rail assembly.
^ Always replace O-ring seals exposed during component service.

CAUTION: DO NOT attempt to remove the fuel inlet fitting on the fuel rail, it is staked in place. To do so will result in damage to the fuel rail or to the internal O-ring seal.
^ Use care in removing the fuel rail assembly, to prevent damage to the injector spray tips and the injector electrical connector terminals.
^ Prevent dirt and other contaminates from entering open lines and passages. Fittings should be capped, and holes plugged, during service.

PROCEDURE:

NOTE: Before removal, the fuel assembly may be cleaned with a spray type engine cleaner, GM X-30A or equivalent, following package instructions. DO NOT immerse the fuel rail in liquid cleaning solvent.

REMOVAL:

1. Disconnect the negative battery cable.
2. Relieve the fuel system pressure, see MAINTENANCE PROCEDURES/FUEL SYSTEM PRESSURE RELIEF.
3. Carefully disconnect the fuel injector electrical connectors.
4. Remove the vacuum hose from the fuel pressure regulator.
5. Disconnect the fuel feed and return lines.
^ Use a back-up wrench on the fuel rail fittings to prevent them from turning.
6. Remove the O-ring seals from the fuel lines and discard.
7. Remove the fuel rail attaching nuts.
8. Remove the fuel rail assembly.

Fuel Rail Assembly Identification:

NOTE: An eight digit number is stamped on the under side of the fuel rail, as shown. Refer to this number if servicing or part replacement is required.

Fuel Rail Assembly Model R630 - Exploded View:

9. Remove the O-ring seals from the tip of each injector and discard.

INSTALLATION:

1. Lubricate new injector O-ring seals with clean engine oil and install on each injector.
2. Position the fuel rail assembly on the intake manifold.
^ Push down on the rail to seat the injectors in the manifold.
3. Install the fuel rail attaching nuts.
^ Tighten to 27.0 Nm (20 (lb.ft).
4. Place new O-ring seals on the fuel feed and return lines.
5. Connect the fuel feed and return lines.
^ Use a back-up wrench on the fuel rail fittings to prevent them from turning.
6. Connect the vacuum hose to the fuel pressure regulator.
7. Connect the fuel injector electrical connectors securely.
8. Connect the negative battery terminal.
9. With the engine OFF and the ignition ON, immediately check for fuel leaks.