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Home >> Saturn >> 2004 >> Ion Red Line >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls (Introduction) >> Description and Operation >> Fuel System Description >> Fuel Pressure Regulator Assembly
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Fuel Pressure Regulator Assembly

The fuel pressure regulator attaches to the fuel return pipe on the fuel sender assembly. The fuel pressure regulator is a diaphragm relief valve. The diaphragm has fuel pressure on one side and regulator spring pressure on the other side. Fuel pressure is controlled by a pressure balance across the regulator. The fuel system pressure is constant and is no longer a function of engine load or manifold vacuum. A software bias compensates the injector on-time based on the signal from the MAP sensor.