Fuel Pressure Regulator

Fuel Pressure Regulator:

The cartridge type fuel pressure regulator is a diaphragm-operated relief valve with fuel pump pressure on one side, and pressure regulator spring and intake manifold vacuum on the other side. The regulator functions to maintain a constant fuel pressure across the injectors at all times. The pressure regulator compensates for engine load by increasing fuel pressure as engine vacuum drops.

The cartridge regulator is serviced as a separate component. When servicing the fuel pressure regulator, insure that the O-ring backup, large O-ring, filter screen, and small O-ring are properly placed on the pressure regulator.

If the fuel pressure is too low, poor performance and a DTC P0171, could result. If the pressure is too high, excessive odor and a DTC P0172, may result. Refer to Fuel System Pressure Test for information on diagnosing fuel pressure conditions.