Lumina V6-204 3.4L DOHC VIN X SFI (1996)
Fuel Pressure Regulator: Description and Operation
Fuel Pressure Regulator
GENERAL DESCRIPTION
The cartridge type fuel pressure regulator (1) is a diaphragm.operated relief valve (6) with fuel pump pressure on one side, and regulator spring (2)
pressure, and intake manifold vacuum on the other side. The regulators function is to maintain a constant fuel pressure across the injectors at all times.
The pressure regulator compensates for engine load by increasing fuel pressure as engine vacuum drops.
The cartridge regulator is serviced as a separate component. When servicing the fuel pressure regulator, insure that the O-ring backup,(3) large
O-ring,(4) filter screen,(5) and small O-ring (7) are properly placed on the pressure regulator.
If the fuel pressure is too low, poor performance and a DTC P0171, could result. If the pressure is too high, excessive odor and a DTC P0172, may
result.