The fuel pressure switch is mounted in the fuel line that runs between the secondary fuel filter and the high pressure fuel pump. The FPS has a 48-58 psi-gauge set- point for detection of a low pressure fuel supply. The PCM de-rated the engine’s power by 30% if the switch is triggered. The FPS protects… Read More »
The fuel supply system uses a Fuel Rail Temperature (FRT) to calculate fuel delivery and fuel pressure switch to help protect the high pressure fuel system.
The secondary fuel filter that is equipped on the vehicle from the factory has three ports. The third port is used during the assembly process. The service part only has two ports: the inlet from the DFCM and the outlet to the VCV inlet which is mounted on the high pressure fuel pump.
To provide additional fuel filtering, an engine mounted secondary fuel filter is located on the top of the left valve cover. The secondary fuel filter is a 4 micron cartridge style filter and is replaced as a complete unit.
The DFCM also includes a WIF sensor that indicates when the reservoir in the water separator is full and needs to be drained. When this occurs, an indicator lamp illuminates and a message appears in the message center.
The water drain valve is located on the bottom of the DFCM. To drain water that has accumulated in the DFCM, turn the drain valve to the open position.
The primary fuel filter is located in the DFCM. The primary fuel filter removes particulates larger than 10 microns from the fuel. The DFCM has a recessed nut on the bottom to remove the fuel filter. The service interval of the fuel filter varies with usage; always consult the Owners Guide or Workshop Manual for… Read More »
The low pressure fuel pump is located inside the DFCM assembly. The low pressure fuel pump draws fuel from the fuel tank through the 10 micron primary fuel filter and pushes it to the engine mounted fuel filter. The fuel pump pressure relief valve is integral to the fuel pump and is not serviceable separately.… Read More »
• The DFCM includes the following components: – low pressure fuel pump – 10 micron primary fuel filter – thermal recirculation valve – water fuel separator (~200ml) – Water in Fuel (WIF) sensor – water drain (manual operation) • After the fuel is conditioned by the DFCM, the clean pressurized fuel is sent to the… Read More »
At key on, the fuel pump within the Diesel Fuel Conditioning Module (DFCM) is turned on and the low pressure fuel system is pressurized. If the engine is not started, the pump runs for up to 30 seconds. The PCM obtains information from the Ambient Air Temperature (AAT), Engine Coolant Temperature (ETC) , Engine Oil… Read More »