Fuel Pressure Regulator: Description and Operation

Fig. 31 Fuel Pressure Regulator:

PURPOSE
Maintains fuel pressure in accordance with manifold pressure.

OPERATION and CONSTRUCTION
The fuel pressure regulator is part of the fuel rail. It maintains the fuel pressure at 299.1 kPa (3.05 kg/cm2, 43.4 psi) above engine vacuum. It utilizes vacuum acting upon a diaphragm to control the amount of fuel pressure allowed to the injectors.