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: For vehicle emission vacuum routing diagrams, refer to SYSTEM DIAGRAM .

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.