Positive Crankcase Ventilation: Testing and Inspection

Diagnostic Chart:

PCV Valve Location:

FUNCTIONAL CHECK
If engine is idling rough, check for a clogged PCV valve or hose. Check the PCV valve identification number to be sure the correct valve is installed. Replace as required.

Use the following procedure to determine if the PCV valve is functioning properly:

1. Remove PCV valve from cam cover grommet.
2. Run engine at idle.
3. Place your thumb over end of PCV valve to check for strong vacuum signal. If there is no vacuum present, check for clogged hose, plugged valve or plugged [1][2]intake manifold port. Replace any clogged components or clean out plugged port.
4. Turn off engine and remove PCV valve from hose. Shake valve and listen for the plugger to rattle inside the valve. If valve does not rattle, replace valve.

OTHER CRANKCASE VENTILATION SYSTEM FAULTS
If there is evidence of engine oil in the throttle body or air cleaner and all the [1][2]PCV components appear and function properly it may indicate excessive crankcase pressure. Refer to "Engine Diagnostic" section in this service manual for specific procedure to perform a crankcase pressure check.