Fuel Pressure Regulator
The pressure regulator is integral to the fuel charging main body and is located near the rear of the air inlet area. It is located so as to nullify the effects of supply line pressure drops and to be insensitive to backpressure in the return line to the tank.
One function of the pressure regulator is to maintain system pressure when the engine and fuel pump are turned off. The regulator functions as a downstream check valve and traps the fuel between itself and the fuel pump.
Maintaining fuel pressure when the engine is turned off, controls fuel line vapor formation and allows for rapid restarts and stable idle operation. The nominal regulated pressure is 14.5 psi (1.0 kg/cm2 ). However, this value may vary from unit to unit. Pressure is adjusted at the factory to compensate for differences in fuel flow among injectors.