Positive Crankcase Ventilation (PCV) System

The PCV system circulates crankcase gases through the intake air system into the engine where they are burned. The PCV system regulates the amount of ventilated air and blowby gases to the intake manifold.

The PCV system on some vehicles will be equipped with a removable PCV valve, a PCV valve integral to the valve cover, or a crankcase ventilation oil separator, as part of the PCV system. The PCV system on some vehicles includes a crankcase pressure sensor to detect a disconnection of the fresh air hose.

The PCV systems comply with OBD PCV monitoring requirements to prevent accidental disconnection from the valve cover. For more information about the PCV monitor and crankcase pressure sensor, refer to Positive Crankcase Ventilation (PCV) System Monitor .