Fuel Pressure Control Solenoid: Description and Operation

Pressure Regulator Control System:

The Pressure Regulator Control Solenoid Valve, located on the right side of the engine compartment near the charcoal canister, is an ECU controlled component of the pressure regulator control (PRC) system.

The PRC system raises fuel pressure to prevent fuel percolation during hot engine restart. Under specified conditions, the ECU energizes the solenoid valve. When energized, the solenoid valve blocks vacuum to the fuel pressure regulator and vents the regulator diaphragm chamber to the atmosphere. This allows the pressure regulator to control fuel pressure without vacuum modulation. Fuel pressure is raised to slightly more than 284 kPa (41 psi).

Under the following conditions, the ECU activates the PRC system for 120 seconds after the ignition is switched "ON" and for 120 seconds after starting:

^ Coolant temperature above 246°F (119°C).
^ Intake air temperature above 167°F (75°C).
^ Engine speed less than 1,500 rpm.