Positive Crankcase Ventilation (PCV) System

DESCRIPTION
The PCV valve is operated by the intake manifold vacuum. When the engine is running at idle, PCV valve is slightly open and a small amount of blowby gas is drawn into the upper intake manifold to be reburned. As the engine speed rises, the PCV valve is opened further, allowing a larger amount of blowby gas to be drawn into the upper intake manifold.