Diesel Data: Automotive Repair

Positive Crankcase Ventilation Valve: Testing and Inspection



Crankcase Ventilation System Inspection/Diagnosis





Notice: Refer to Fuel Vapors in Evaporative Emission (EVAP) Components Caution.

1. Blow air into the cylinder head side of the PCV valve.
2. Check that air passes through the PCV valve easily.




3. Blow air into the intake manifold side of the PCV valve.
4. Check that air passes through the PCV valve with high resistances.
5. If the PCV valve fails either test, replace the PCV valve.