Fuel Charging and Controls

The fuel injection supply manifold - gasoline:
^ delivers fuel to the fuel injector.
^ receives fuel from the fuel supply line.
^ returns unused fuel to the fuel tank through the fuel return line.

The fuel shut-off solenoid:
^ is normally closed.
^ opens when the key is in the run or start position.
^ shuts off the fuel supply if the vehicle is shut off or if the inertia fuel shut-off is triggered.

The throttle body:
^ controls air supply to the upper intake manifold by positioning the throttle plate.
^ connects the accelerator cable and, if equipped the speed control actuator cable to the throttle plate.
^ is not adjustable.
^ cannot be cleaned.

The fuel injector:
^ uses the replacement O-rings if needed.
^ is electrically operated by the Powertrain Control Module (PCM).
^ has an internal solenoid that opens a needle valve to inject fuel into the lower intake manifold.
^ atomizes the fuel as the fuel is delivered.
^ is deposit resistant.

The fuel pressure relief valve:
^ is used to inspect and relieve fuel pressure.

The fuel pressure regulator:

CAUTION: Use O-rings that are made of special fuel-resistant material. Use of ordinary O-rings can cause the fuel system to leak. Do not reuse O-rings.

^ maintains a constant fuel pressure throughout the fuel system and to the fuel injector.
^ is spring-loaded and operated by the intake manifold vacuum.

The fuel injection supply manifold - natural gas:
^ delivers fuel to the fuel injector.
^ receives fuel from the fuel supply line.
^ provides mounting surfaces for the fuel temperature sensor and the fuel pressure sensor.
^ provides mounting surface for the main fuel shut-off solenoid.