Diesel MFI Pump: Description and Operation

FUEL INJECTION PUMP




The fuel injection pump is a mechanical high pressure pump. The fuel injection pump is located below the intake manifold. Fuel is pumped to the fuel rails at a specified pressure. Fuel pressure is regulated by a valve on the inlet of the fuel pump, controlled by the engine control module (ECM). Excess fuel from the fuel injection pump returns to the fuel tank through the fuel return pipe and a fuel cooler.