Positive Crankcase Ventilation: Testing and Inspection

System inspection

NOTE: Disconnecting the valve while the engine coolant is warm over 2O°C (68°F) may create a vacuum leak (through the valve) large enough to cause difficult starting.

1. Verify that the engine coolant temperature is below 20°C (68°F).
2. Start the engine and let it idle.
3. Disconnect the PCV valve from the cylinder head coven
4. Block the valve opening by hand and verify that vacuum is felt.
5. If not check the PCV valve for clogging and damage. If the hose is OK, replace the PCV valve.