Excursion 2WD V8-5.4L SOHC VIN L (2000)
Fuel Pressure Regulator: Description and Operation
Fuel Pressure Regulator
Fuel Pressure Regulator
The fuel pressure regulator is attached to the fuel rail downstream of the fuel injectors. It regulates fuel pressure supplied to the fuel injectors. The
regulator is a diaphragm-operated relief valve. One side of the diaphragm senses fuel pressure and the other side is connected to the intake manifold
vacuum. Fuel pressure is established by a spring preload applied to the diaphragm. Balancing one side of the diaphragm with manifold vacuum
maintains a constant fuel pressure drop across the fuel injectors. Fuel pressure is high when engine vacuum is low. Excess fuel is bypassed through the
fuel pressure regulator and returned through the fuel return line to the fuel tank.
