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Positive Crankcase Ventilation: Testing and Inspection

Fig. 149 PCV:






1. Warm engine to normal operating temperature and run at idle.
2. Disconnect valve, together with ventilation hose, from cylinder head cover.
3. Block valve opening and verify that vacuum is felt.

Fig. 150 PCV Test:






4. Remove valve.
5. Blow through from port "A" and verify that air comes out port "B".
6. Blow through from port "B" and verify that air does not come out port "A".
7. Replace valve if necessary.