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Positive Crankcase Ventilation: Testing and Inspection

Positive crankcase ventilation (PCV) System check
1. Warm up engine to normal operating temperature.
2. Run engine at idle.
3. Disconnect PCV valve ventilation hose from cylinder head cover.
4. Block PCV valve opening.




5. Verify that vacuum is felt.
6. Remove PCV valve.
7. Blow through valve from port "A" and verify that air comes out of port "B".
8. Blow through valve from port "B" and verify that no air comes out of port "A".




9. Replace the PCV valve if necessary.