Fuel Pump: Description and Operation

Fuel Pump Assembly:

Fuel Tank Assembly:

PURPOSE
Provide high pressure (64 - 85 psi / 441 - 589 kPa) fuel to injection system. To ensure adequate supply, pump circulates more than required maximum fuel amount at higher than required pressure.

LOCATION
Inside fuel tank.

OPERATION
While engine is running, pump runs constantly. Fuel delivery system is a loop, with fuel not used by the engine routed back to the tank. When ignition is switched on, ECU runs pump for about 2 seconds to pressurize system in preparation for starting.

CONSTRUCTION
High pressure, positive displacement pump. Pump is installed as part of the in-tank fuel gauge unit and has a filter screen attached to its inlet to remove larger particle contaminants.