Pressure Regulator Assembly

The pressure regulator assembly is a diaphragm operated relief valve with fuel pump pressure on one side, and regulator spring pressure. The regulator maintains a constant pressure differential across the fuel injectors at all times by the amount of pressure it takes to lift the diaphragm off its seat.

Spring pressure controls fuel pressure. This spring is preset at the factory and no adjustment is required. The fuel pressure regulator is located on the fuel rail just in front of the fuel rail and fuel return line.

With ignition in On position and engine Off, fuel pressure at pressure test port should be 380 kPa (44 psi). If pressure is lower than specification, excessive odor and a DTC P0172 may set. Refer to "Fuel System Testing" for fuel pressure diagnosis.