System Description

PCM turns on the in-tank fuel pump when ignition is on. The fuel pump will remain on as long as engine is cranking or running and PCM is receiving ignition reference pulses. If there are no ignition reference pulses, PCM will turn the fuel pump off 2 seconds after ignition is turned on or 2 seconds after engine stops running. The fuel pump is attached to fuel sender assembly and is designed to provide fuel at a pressure above the pressure needed by the fuel injectors. A fuel pressure regulator, attached to fuel rail, keeps fuel available to fuel injectors at a regulated pressure. Unused fuel is returned to fuel tank by a separate fuel return pipe.