Purge Control System Inspection
- Disconnect Red-striped vacuum hose from purge control solenoid valve at throttle body. Plug throttle body fitting. Connect a hand-held vacuum pump to Red-striped vacuum hose. Plug fitting at throttle body where Red-striped vacuum hose was connected.
- With engine cold and coolant temperature less than 140°F (60°C), start engine and let idle. Apply 15 in. Hg vacuum. Ensure vacuum holds. Increase engine speed to 3000 RPM. With vacuum maintained at 15 in. Hg, vacuum should still hold. Warm engine until coolant temperature is greater than 158°F (70°C).
- Within 3 minutes after starting engine, increase engine speed to 3000 RPM. Using hand-held vacuum pump, try applying vacuum. Ensure vacuum does not hold. Reduce engine speed to idle. With engine idling, apply 15 in. Hg vacuum. Ensure vacuum holds.NOTE: When performing next step, if altitude is greater than 7200 feet or intake air temperature is greater than 122°F (50°C), vacuum will leak continuously.
- After 3 minutes have elapsed from starting engine, increase engine speed to 3000 RPM. Apply 15 in. Hg vacuum. Vacuum should hold momentarily then leak.
- If purge control system does not function as described, perform individual component testing.