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Positive Crankcase Ventilation: Description and Operation

PCV System:





Typical PCV Air Flow Diagram:






PURPOSE
The Positive Crankcase Ventilation (PCV) System cycles crankcase gases back through the engine where they are burned.


OPERATION
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.

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