Positive Crankcase Ventilation Valve: Testing and Inspection

PCV Test-Typical:

WARNING: APPLY PARKING BRAKE AND/OR BLOCK WHEELS BEFORE PERFORMING ANY TEST OR ADJUSTMENT WITH THE ENGINE OPERATING.

With the engine idling, remove the PCV valve from its attaching point. If the valve is operating properly, a hissing noise will be heard and a strong vacuum felt when placing a finger over the valve inlet. With the engine off, shake the valve. The valve should rattle when shaken. Replace the valve if it does not operate properly. Do not attempt to clean the PCV valve.