Fuel Charging and Controls

The fuel injection supply manifold:

• Delivers fuel to the individual fuel injector.
• Receives fuel from the fuel supply line.

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 lever.
• Is not adjustable.
• Cannot be cleaned.

The fuel injectors:

• Are electrically operated by the powertrain control module (PCM).
• Atomize the fuel as the fuel is delivered.
• Are deposit-resistant.
• Each have an internal solenoid that opens a needle valve to inject fuel into the lower intake manifold.

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

The fuel pulse damper:

• Maintains constant fuel pressure throughout the fuel system and to the fuel injectors.
• Is spring-loaded and operated by intake manifold vacuum.

The A/C compressor clutch control relay (if A/C equipped):

• Is controlled by the PCM.
• Interrupts A/C clutch operation during engine start or manual transmission clutch engagement to reduce engine load.

The fuel pump relay engages the fuel pump when energized by the PCM.