Positive Crankcase Ventilation Valve Check
- Hold the positive crankcase ventilation (PCV) valve with the vacuum side down. Insert a thin rod, and using light pressure, depress the end of the PCV valve spring by 5 - 10 mm (0.2 - 0.3 inch). Release pressure on the rod to see if the PCV valve spring will lift the rod to its original position.
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
- If the rod returns quickly to its original position, the PCV valve is OK. If the stick does not return quickly, clean or replace the PCV valve.