Positive Crankcase Ventilation: Testing and Inspection

Fig. 163 PCV Test:

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