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Home >> GMC >> 1998 >> Forward Control 6.5 F >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System & Component Testing - 4.3L >> Fuel System >> Fuel Delivery >> Fuel Pressure Regulator (CSI)
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Fuel Pressure Regulator (CSI)

Fuel pressure regulator is mechanically controlled by internal spring pressure. Regulator is adjusted at factory and is not serviceable. If fuel pressure is too low, check for restricted delivery line. Also, check fuel pump pressure and volume. If fuel pressure is too high, check for restricted fuel tank return line or fuel filter. If no faults are found and pressure is too high or too low, replace fuel pressure regulator.