Engine Emission Control: Overview: PCV
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 vacuum routing diagrams are contained in the Description and Operation subsection of the Evaporative Emissions article. REFER to
EVAPORATIVE EMISSIONS
The engine emission control system consists of the PCV system.
The PCV system:
- uses intake manifold vacuum to ventilate blow-by vapors from the crankcase.
- returns the vapors to the intake manifold for combustion.
The PCV system consists of the:
- crankcase ventilation tube.
- PCV valve.
The crankcase ventilation tube:
- is connected to the PCV valve and the intake manifold fitting.
The PCV valve:
- varies the amount of blow-by vapors returned to the intake manifold based on available engine vacuum.
- serviced as part of the crankcase vent oil separator.