High Pressure Fuel Pump
DESCRIPTION
High pressure fuel lines deliver diesel fuel under extreme pressure from the injection pump to the fuel injectors. This may be as high as 1800 bar (26, 106 psi). Use extreme caution when inspecting for high pressure fuel leaks. Fuel under this amount of pressure can penetrate skin causing personal injury or death. Inspect for high pressure fuel leaks with a sheet of cardboard. Wear safety goggles and adequate protective clothing when servicing fuel system.
Cranking the engine for an extended time without a fuel supply may damage the fuel injection pressure pump.
| 1 - High Pressure Fuel Pump Bolts |
| 2 - High Pressure Fuel Pump |
The High Pressure Fuel Pump (HPFP) is mounted to the cylinder head and there is a protection blocker plate attached to the front of the high pressure fuel pump.
| 1 - Fuel Quantity Solenoid |
| 2 - Fuel Quantity Solenoid Screws |
The only serviceable parts on the High Pressure Fuel Pump (HPFP) is the Fuel Quantity Solenoid (FQS), the drive gear, and the O-ring.
OPERATION
The High Pressure Delivery Pump (HPDP) supplies pressurized fuel between 200-1800 bar (2, 900 - 26, 106 psi) to the fuel rail and fuel injectors. The cascade valve, located inside the HPDP regulates the pressure in the low side and diverts some of the fuel entering for lubrication of the pump. The Powertrain Control Module (PCM) monitors high side fuel pressure via a fuel pressure sensor. Based on readings from the fuel pressure sensor, the PCM controls the output pressure of the pump using the Fuel Quantity Solenoid (FQS), which mounts to the HPDP.
The high pressure pump must not be disassembled or opened. The high pressure pump has a screen filter that is not serviceable. If diagnosis has led you to believe that the filter is restricted or plugging up then the high pressure pump needs to be replaced.