Positive Crankcase Ventilation: Description and Operation

Crankcase Ventilation System Description

A closed crankcase ventilation system provides a more complete scavenging of crankcase vapors. Fresh air from the throttle body is supplied to the crankcase, mixed with blow-by gases, and then passed through a crankcase ventilation pipe/passage into the intake manifold.

Results of Incorrect Operation

A plugged positive crankcase ventilation (PCV) pipe/passage way may cause any of the following conditions:

^ Rough idle
^ Stalling or slow idle speed
^ Oil leaks
^ Sludge in engine