Fuel System - Overview: Notes

WARNING: This page is about a different car, the 2019 Ford F-550 Super Duty, 2019 Ford F-450 Super Duty, 2019 Ford F-350 Super Duty, and 2019 Ford F-250 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Repairs of the fuel system are to be achieved only by replacement of the failed component(s). Repair of a fuel system component should not be attempted.

NOTE: If directed during assembly of fuel system components, lubricate any seal(s) only with specified material. Failure to follow this instruction may result in seal failure and fuel leakage.

The diesel fuel system consists of the following:

Fuel tubes
Fuel filters (located on the engine and on the fuel tank)
Fuel level sensor
Fuel tank filler pipe assembly
Fuel tank
In tank diesel delivery module
Externally mounted fuel filter and water separator

The fuel system for the high-pressure common rail direct injection turbocharged diesel engine:

is controlled by the PCM.

The electric FP (located in the diesel delivery module in the tank):

draws fuel from the fuel tank through a external fuel tank mounted filter.
circulates fuel at low vacuum through the 10 micron externally mounted fuel tank filter to the engine mounted secondary fuel filter and fuel injectors to initially fill the hydraulic couplers. The fuel is filtered through a 4 micron engine mounted secondary fuel filter, and then supplied to the high-pressure fuel injection pump. Fuel is returned from the injectors through the fuel injector return hose and combines with fuel being supplied to the inlet of the engine mounted secondary fuel filter. Fuel that is returned from the fuel rail combines with fuel being returned from the high-pressure fuel injection pump and passes through the frame mounted fuel cooler to the diesel fuel conditioning module. The externally mounted fuel tank filter contains a thermal recirculating valve that, based on fuel temperature, allows the returning fuel to be sent back to the fuel tank.