Fuel Pressure Control Solenoid: Description and Operation

Fuel Pressure Regulator Control Chart:

PRVR-Control Solenoid Valve:

PURPOSE
To allow better engine starting after "hot-soaks". Nissan refers to this component as the Pressure Regulator Vacuum Relief (PRVR) Solenoid.

PRVR Operation:

OPERATION
When fuel temperature, as measured in the fuel rail, exceeds 79° C (167° F), the solenoid valve responds to the ON/OFF signal from the Engine Control Module (ECM). When it is OFF, a vacuum signal from the intake manifold is fed into the pressure regulator. When the ECM sends an ON signal, the coil pulls the plunger downward and cuts the vacuum signal. This increases the fuel pressure, allowing easier starting.
The ECM will ground the circuit to the PRVR for up to 30 seconds.