Pressure Regulator Control
- Engine must be at operating temperature (150°-200°F (66°-93°C)) and ambient temperature must be high. Turn engine off. Disconnect vacuum hose at fuel pressure regulator and connect a vacuum gauge to hose.
- Without touching throttle, start engine. Observe vacuum gauge. Vacuum should not exist for a period of 1-3 minutes. If vacuum is present, check vacuum routing, pressure regulator control solenoid, and related circuits.
- If vacuum gauge shows intake manifold vacuum after specified amount of time, system is okay. See Figure . If intake manifold vacuum is not present after 3 minutes, check vacuum source, pressure regulator control solenoid and related circuits.