Fuel Rail: Service and Repair

WARNING: To reduce the risk of fire and personal injury, it is necessary to relieve the fuel system pressure before servicing fuel system components. See MAINTENANCE PROCEDURES/FUEL SYSTEM PRESSURE RELIEF.

After relieving system pressure, a small amount of fuel may be released when servicing fuel lines or connections. In order to reduce the chance of personal injury, cover fuel line fittings with a shop towel before disconnecting, to catch any fuel that may leak out. Place the towel in an approved container when disconnect is complete.

To reduce the risk of fire and personal injury that may result from a fuel leak, always replace "O" ring seals exposed during component service.

NOTE: 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 electrical connector terminals and the injector spray tips.

Prevent dirt and other contaminates from entering open lines and passages. Fittings should be capped, and holes should be plugged, during servicing.

Before removal, the fuel rail assembly may be cleaned with a spray type cleaner, GM X30-A or equivalent, following package instructions. Do Not immerse fuel rails in liquid cleaning solvent.

REMOVAL:

Fuel Rail Assembly Removal:

1. Disconnect the negative battery terminal.
2. Relieve fuel system pressure. See MAINTENANCE PROCEDURES/FUEL SYSTEM PRESSURE RELIEF.
3. Remove crankcase ventilation oil/air separator.
4. Remove injector electrical connectors:
^ Push in wire clip, while pulling connector away from the injector.
5. Disconnect the vacuum hose at the fuel pressure regulator.
6. Remove fuel rail attaching bolts.
7. Remove the fuel rail assembly from the cylinder head.

^ Continue, if complete removal is required.

8. Remove the fuel inlet pipe from the fuel rail.
^ Use a back-up wrench on the fuel rail inlet fitting to prevent it from turning.
9. Remove the fuel return tube retainer screw and retainer.
10. Disconnect the fuel outlet pipe from the fuel pressure regulator.

Fuel Rail Assembly:

DISASSEMBLY:

NOTE: If an injector becomes separated from the fuel rail and remains in the cylinder head, both injector "O" ring seals and the retainer clip must be replaced.

1. Remove the injector "O" ring seal from the spray tip end of each injector, and discard.
^ If an injector was separated from the fuel rail during removal, remove both "O" rings.
2. Remove the injector retainer clips, if necessary.

^ Continue, if fuel pipes were disconnected from the fuel rail.

3. Remove the fuel inlet and return tube seal retainers and tube seals.
a. Use a small screwdriver to pry out seal retainers.
b. Discard seals and retainers.

ASSEMBLY:

1. Lubricate new injector "O" ring seals with clean engine oil, and install injectors.
2. Install new injector retainer clips, if necessary.

^ Continue, if fuel pipes were disconnected from the fuel rail.

3. Install the new fuel inlet and return tube seals and retainers.
4. Press the retainer into contact the "O" ring.

INSTALLATION:

1. If separated from the fuel rail, install the injectors into the fuel rail injector sockets, with the electrical connector facing outward.
^ Push in far enough to engage the retainer clip with machined slots on the rail socket.
2. If the fuel pipes were disconnected from the fuel rail, reconnect them at this time.
a. Tighten the return tube retainer screw to 6.0 Nm (53 lb.in).
b. Tighten the fuel inlet pipe nut to 30 Nm (22 lb.ft).
c. Use a back-up wrench on the fuel rail inlet fitting to prevent it from turning.
3. Position the fuel rail assembly into cylinder head.
4. Install fuel rail assembly attaching bolts.
^ Tighten bolts to 26 Nm (19 lb.ft).
5. Connect the injector electrical connectors.
^ Rotate the injectors as required to avoid stretching the wire harness.
6. Attach vacuum hose to the pressure regulator.
7. Connect crankcase ventilation oil/air separator.
8. Connect the negative battery terminal.
9. With the engine "OFF" and the ignition switch "ON" immediately check for fuel leaks.