Fuel Pump
An in-tank electric fuel pump delivers fuel to injectors through an in-line fuel filter. The pump is designed to supply fuel pressure in excess of vehicle requirements. The pressure relief valve in the fuel pump controls maximum fuel pump pressure.
A pressure regulator mounted in fuel rail, keeps fuel to injectors at a constant pressure. Excess fuel is returned to fuel tank through regulator return line. For fuel pressure specifications, see appropriate SERVICE & ADJUSTMENT SPECIFICATIONS article.
When the ignition switch is turned to ON position, PCM will turn on the electric fuel pump by energizing the fuel pump relay. The PCM will continue to energize relay if the engine is running or cranking (PCM is receiving reference pulses from the ignition control module). If no reference pulses exist, PCM de-energizes fuel pump relay within 2 seconds after ignition is turned on. For additional information, see FUEL PUMP RELAY .