Positive Crankcase Ventilation: Description and Operation

PURPOSE
The Positive Crankcase Ventilation (PCV) system is a closed system. This means that oil vapors and unburned hydrocarbons do not enter the atmosphere.


OPERATION
During high vacuum conditions such as idle, the pollutants are drawn into the intake manifold via the check valve. When the throttle is opened at low vacuum, the pollutants are drawn into the intake side of the turbocharger via the pressure control valve.