Positive Crankcase Ventilation Valve: Testing and Inspection

Checking PCV Valve:

1. Warm up the engine to the normal operating temperature and run it at idle.
2. Disconnect the PCV valve together with the ventilation hose from the cylinder head cover.
3. Block the valve opening and verify that vacuum is felt.
4. Remove valve and blow through it from both directions. Verify that air will flow through valve in one direction only (toward the intake manifold).
5. Replace valve if necessary.