Positive Crankcase Ventilation (PCV) Valve: Inspection

Disconnect the ventilation hose from the positive crankcase ventilation (PCV) valve. Remove the PCV valve from the rocker cover and reconnect it to the ventilation hose.
Run the engine at idle and put a finger on the open end of the PCV valve, making sure that intake manifold vacuum is felt.
If vacuum is not felt, clean the PCV valve and ventilation hose in cleaning solvent or replace if necessary.

Fig 1: Disconnecting The Ventilation Hose From The Positive Crankcase Ventilation (PCV) Valve
Courtesy of KIA MOTORS AMERICA, INC.

Fig 2: Testing PCV System For Vacuum
Courtesy of KIA MOTORS AMERICA, INC.

NOTE: The plunger inside the PCV valve will move back and forth.
Clean the PCV valve and ventilation hose with cleaning solvent or replace if necessary.