Hombre S Regular Cab 4WD V6-4.3L (1999)
Fuel Pressure Regulator: Description and Operation
Fuel Pressure Regulator
The fuel pressure regulator (1) is a diaphragm-operated cartridge relief valve with the fuel pump pressure on one side and the regulator spring pressure
and intake manifold vacuum on the other. A retainer (2) holds the fuel pressure regulator.
The regulator's function is to maintain a constant pressure differential across the injectors at all times. The pressure regulator compensates for engine
load by increasing the fuel pressure as engine vacuum drops.
With the ignition ON leaving the engine OFF (zero vacuum), the fuel pressure at the pressure test connection should be 415 - 455 kPa (60 - 66 psi). If
the pressure is too low, poor performance could result. If the pressure is too high, excessive odor may result. The Fuel System Diagnosis has information
on diagnosing fuel pressure conditions. Refer to Fuel System Diagnosis.
