Positive Crankcase Ventilation: Description and Operation

Crankcase Ventilation System Description

A crankcase ventilation system is used to consume crankcase vapors during the combustion process instead of venting them to the atmosphere. Fresh air is supplied to the crankcase. The fresh air hose is connected to the throttle body and the right side valve rocker cover. The crankcase mixes the fresh air with the blow-by gases and passes the mixture through a fixed non-serviceable orifice. The orifice is integrated into the engine valley cover. The dirty air hose connects to the intake manifold, for vacuum, and the engine valley cover. If abnormal operating conditions arise, the system is designed to allow excessive amounts of blow-by gases to back flow through the crankcase ventilation fresh air tube in order to be consumed by normal combustion.