In order to maintain the stability of idling speed, the PCV valve closes the flushing stream during deep intake of inlet tubes, the valve failure may cause the engine to stop or to speed up the revolutions. Defective crankcase ventilation system can lead to stability and idling speed reduction, including engine stopping, oil leak development, blurb formation on the inner surfaces of the aggregate.
To check the operation of the PCV valve, first disconnect the ventilation hose, remove the valve from the engine.
After removal of the valve it is necessary to reconnect the ventilation hose to it, start the engine at idling speed, and squeeze the finger to the opening in the valve. Inside the details, the vacuum must be felt.
If the vacuum is not felt, the hose must be checked first, then (if hose is in order), check out the engine, release the valve from the hose, and use the thin rod to check the freedom of its plunger: the rod is entered in the opening with the carved side of the part. In case of shaking, the proper valve shall be able to produce a cracking.