Fuel Pressure Regulator: Description and Operation

Pressure Regulator Control System:

PURPOSE
The pressure regulator varies fuel pressure within specified levels for efficient engine operation. The (fuel) pressure regulator is also part of the pressure regulator control (PRC) system. The PRC system enables the powertrain control module engine (PCME) to raise fuel pressure for improved hot and cold engine starts.

CONSTRUCTION
The pressure regulator uses a spring loaded diaphragm that has manifold vacuum ports on both sides of the diaphragm. The diaphragm is connected to a valve which controls fuel pressure "bleed off" back to the fuel tank.


OPERATION
Manifold vacuum for the regulator diaphragm ports is routed through two PRC solenoid valves. The pressure regulator diaphragm moves in response to changes in vacuum supply to either side of the diaphragm. The pressure regulator changes fuel pressure in direct response to engine vacuum fluctuations and the operation of the PCME controlled PRC solenoid valves.