Fuel Pressure Regulator
- Relieve fuel pressure from system. Connect fuel pressure gauge in line between fuel filter and fuel rail. Remove vacuum hose from fuel pressure regulator and plug hose. Connect hand-held vacuum pump to pressure regulator. Start engine and let idle.
- Gradually apply vacuum to regulator. Fuel pressure should decrease as vacuum increases. Compare values to FUEL PRESSURE table in BASIC TESTING article in the ENGINE PERFORMANCE Section. If results are unsatisfactory, replace fuel pressure regulator.