Positive Crankcase Ventilation Valve: Testing and Inspection

PCV SYSTEM

WARNING: apply parking brake and/or block wheels before performing any test or adjustment with the engine operating.

1. Remove the make-up air hose from the air plenum at the rear of the engine. Hold a piece of stiff paper (parts tag) loosely over the end of the make-up air hose.
2. After allowing approximately one minute for crankcase pressure to reduce, the paper should draw up against the hose with noticeable force. If the engine does not draw the paper against the hose end Inspect the PCV valve and hose for blockage.
3. Turn the engine off. Remove the PCV valve from the valve cover. The valve should rattle when shaken.
4. Replace the PCV valve and retest the system if it does not operate as described in the preceding tests. Do not attempt to clean the old PCV valve.