Positive Crankcase Ventilation: Description and Operation

PCV System Flow Schematic:

Typical PCV Valve:

Typical PCV Vacuum Connector:

The Positive Crankcase Ventilation (PCV) System cycles crankcase gases back through the engine where they are burned. The PCV valve regulates the amount of ventilating air and blow-by gas to the intake manifold and prevents backfire from traveling into the crankcase. The PCV valve should be mounted in a vertical position. On some applications, the PCV system is connected to the evaporative emission system (refer to the VECI decal).

CAUTION:
Do not remove the PCV system from the engine. Removal of the PCV system will adversely affect the fuel economy and engine ventilation and result in shorter engine life.