Positive Crankcase Ventilation: Testing and Inspection

Fig. 56 Positive Crankcase Ventilation System:

1. Disconnect the PCV hose from the air cleaner.
2. Run the engine at idle.
3. Place your thumb over the end of the PCV hose and check for vacuum. If vacuum is not present check for a restricted, cracked, or broken hose, or restricted calibrated orifice at the idle air distributor.