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Positive Crankcase Ventilation: Testing and Inspection

Positive Crankcase Testing Procedures

1. Warm up the engine to the normal operating temperature and run it at idle.
2. Disconnect the PCV valve with the ventilation hose from the cylinder head cover.




3. Block the valve opening and inspect that there is vacuum.
4. Replace the PCV valve as necessary.

PCV Valve:




5. Remove the PCV valve
6. Blow through the valve from port A and verify that air comes out of port B.
7. Blow through the valve from port B and verify that no air comes out of port A.
8. Replace the PCV valve as necessary.