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Fuel Rail & Injectors: Installation

WARNING: This page is about a different car, the 2003 Pontiac Bonneville, 2003 Buick Park Avenue, and 2003 Buick LeSabre. However, it is still accessible from the selected car via links, so may be relevant.
WARNING: In order to reduce the risk of fire and personal injury that may result from a fuel leak, always install the fuel injector "O" rings in the proper position. If the upper and lower "O" rings are different colors (Black and Brown), be sure to install the Black "O" ring in the upper position and the Brown "O" ring in the lower position on the fuel injector. The "O" rings are the same size but are made of different materials.
  1. Lubricate the new injector upper "O" ring seal with clean engine oil. Install the new injector "O" ring seal on the injector. Install retainer clip on the injector. Push the fuel injector into the fuel rail injector socket with the electrical connector facing outward. The retainer clip locks on to a flange on the fuel rail injector socket.
  2. "O" rings must be replaced on all components that are serviced. Lightly oil the fuel injector "O" rings with clean engine oil. Place the fuel rail assembly on the intake manifold. Seat the fuel injectors by hand. Install the fuel rail hold-down bolts.
  3. Tighten the fuel rail hold-down bolts to specification. See TORQUE SPECIFICATIONS . Connect the 6 fuel injector electrical connectors. Connect the fuel feed and return pipes to the fuel rail tubes. Connect the vacuum line to the fuel pressure regulator. Install the ignition coil wires.
  4. Tighten the fuel fill cap. Connect the negative battery cable. Perform the following procedure in order to inspect for leaks. Turn ON the ignition for 2 seconds. Turn OFF the ignition for 10 seconds. Turn ON the ignition. Inspect for fuel leaks. Install the fuel injection sight shield.


WARNING: In order to reduce the risk of fire and personal injury that may result from a fuel leak, always install the fuel injector "O" rings in the proper position. If the upper and lower "O" rings are different colors (Black and Brown), be sure to install the Black "O" ring in the upper position and the Brown "O" ring in the lower position on the fuel injector. The "O" rings are the same size but are made of different materials.
  1. Lubricate the new injector upper "O" ring seal with clean engine oil. Install the new injector "O" ring seal on the injector. Install retainer clip on the injector. Push the fuel injector into the fuel rail injector socket with the electrical connector facing outward. The retainer clip locks on to a flange on the fuel rail injector socket.
  2. The "O" rings must be replaced on all components that are serviced. Lightly oil the fuel injector "O" rings with clean engine oil. Place the fuel rail assembly on the intake manifold. Seat the fuel injectors by hand. Install the fuel rail hold-down nuts. Tighten the fuel rail hold-down nuts to specification. See TORQUE SPECIFICATIONS .
  3. Install the fuel injector electrical harness clips holding harness to the front of fuel rail. Connect the 6 fuel injector electrical connectors. Install the bypass valve actuator. See Figure. Install the rear generator mounting bracket with the EVAP canister purge solenoid valve. Install the ignition coil wires to the retainer clips to the top of supercharger. Connect the vacuum line to the fuel pressure regulator.
  4. Connect the fuel feed pipe and return pipe to the fuel rail. Connect the negative battery cable. Perform the following procedure in order to inspect for leaks. Turn ON the ignition for 2 seconds. Turn OFF the ignition for 10 seconds. Turn ON the ignition. Inspect for fuel leaks. Install the fuel injection sight shield.