When servicing the fuel rail assembly, be careful to prevent dirt and other contaminants from entering the fuel passages. Fittings should be capped and holes plugged during servicing. Any time the fuel system is opened for service, the O-ring seals and retainers used with related components should be replaced.
Before removing the fuel rail, the fuel rail assembly may be cleaned with a spray type cleaner, Delco-X30A or equivalent, following package instructions. Do not immerse fuel rails in liquid cleaning solvent. Be sure to always use new O-rings and seals when reinstalling the fuel rail assemblies.
There is an 8-digit number stamped on the left side fuel rail on dual rail assemblies (fueling even cylinders No. 2, 4, 6). Refer to this number if servicing or part replacement is required.
REMOVAL & INSTALLATION
- Relieve fuel system pressure. Disconnect the negative battery cable. Remove the decorative cover.
- Disconnect the fuel feed line and return line from the fuel rail assembly. If applicable, be sure to use a backup wrench on the inlet fitting to prevent turning. If the new style fuel lines are used, squeeze the tabs and pull the lines off.
- Remove the vacuum line from the pressure regulator.
- Disconnect the electrical connectors from each fuel injector.
- Remove the bolts retaining the fuel rail assembly to the intake manifold. Remove the fuel rail assembly and cover all openings with masking tape to prevent dirt entry.
If any injectors become separated from the fuel rail and remain in the intake manifold, both O-ring seals and injector retaining clip must be replaced. Use care in removing the fuel rail assembly, to prevent damage to the injector electrical connector terminals and the injector spray tips. When removed, support the fuel rail to avoid damaging its components. Fuel injectors are serviced as a complete unit only. Since it is an electrical component, it should not be immersed in any type of cleaner.
- Lubricate all the O-rings and seals with clean engine oil.
- Carefully push the injectors into the cylinder head intake ports until the bolt holes on the fuel rail and manifold are aligned. Torque the fuel rail retaining bolts to 19 ft. lbs. (27 Nm).
- Connect the electrical connectors to each fuel injector.
- Connect the vacuum line to the pressure regulator. Install the decorative cover.
- Connect the fuel feed line and return line to the fuel rail assembly. If used, be sure the snap lock connectors are properly seated.
- Connect the negative battery cable, energize the fuel pump, and check for fuel leaks. To accomplish this safely, apply battery voltage to the fuel pump prime connector located at the right front corner of the engine compartment, between the battery and the horn. The connector is a single-terminal type with a gray wire in 1990 and a red wire in later years.