Positive Crankcase Ventilation: Description and Operation

The positive crankcase ventilation system consists of a valve and several hoses.

The positive crankcase ventilation system recycles crankcase gases back through the engine where they mix with the incoming air/fuel charge.

The positive crankcase ventilation valve regulates the amount of ventilation air and crankcase gas supplied to the intake manifold and also prevents backfiring into the crankcase.

The positive crankcase ventilation system helps to reduce hydrocarbon emissions from the engine.