Fuel Pressure Regulator

The fuel pressure regulator is a diaphragm-operated relief valve with injector pressure on one side and manifold pressure on the other. The function of the regulator is to maintain constant fuel pressure at injectors at all times. The pressure regulator also compensates for engine load by increasing fuel pressure when low manifold vacuum is experienced.

The pressure regulator is mounted on the fuel rail and is serviced separately. If pressure is too low, poor performance could result. If the pressure is too high, excessive odor and a code 45 may result. See Figure .