Fuel Metering System

BASIC SYSTEM OPERATION
The fuel metering system starts with the fuel in the fuel tank. An electric fuel pump, located in the fuel tank with the gage sending unit, pumps fuel to the fuel rail through an in-pipe fuel filter. The pump is designed to provide fuel at a pressure above the pressure needed by the injectors. A pressure regulator in the fuel rail keeps fuel available to the injectors at a constant pressure. Unused fuel is returned to the fuel tank by a separate pipe. For further information on the fuel tank, in-pipe filter, and fuel pipes, refer to system components.

AIR/FUEL METERING SYSTEM COMPONENTS:

The air/fuel metering system is made up of the following parts:

- Fuel injectors.
- Throttle body.
- Fuel rail.
- Fuel pressure regulator.
- PCM.
- Crankshaft position sensor and ignition control module.
- Camshaft position sesor and ignition control module.
- Idle Air Control (IAC) valve.
- Fuel pump.
- Fuel pump relay.