Skylark L4-138 2.3L DOHC VIN D MFI (1988)
Fuel Pressure Regulator: Description and Operation
Fig. 4 Fuel pressure regulator
The pressure regulator is a diaphragm type relief valve with injector pressure acting on one side of the diaphragm and manifold and spring pressure
acting on the other, Fig. 4. The regulator maintains control pressure in the fuel rail by controlling flow in the return line. The pressure regulator also
serves as a load compensator by increasing fuel pressure at times of low manifold vacuum.
