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Engine Emission Control - Overview: Overview

NOTE: Do not permanently remove or render inoperative any part of the vehicle emission control system including related hardware. Failure to comply may violate applicable state and federal laws.
NOTE: The vehicle emission routing diagrams are contained in the Description and Operation subsection of the Evaporative Emissions.

Refer to: EVAPORATIVE EMISSIONS - SYSTEM OPERATION AND COMPONENT DESCRIPTION .

The PCV  system uses intake manifold vacuum to ventilate blow-by vapors and evaporated oil from the crankcase and returns them to the intake manifold for combustion. The PCV  valve varies the amount of blow-by vapors and evaporated oil returned to the intake manifold.