4.8.1 Description

The engine is ventilated through a part load and a full load breather. The part load breather is a flexible composite hose connected between the positive crankcase ventilation (PCV) valve mounted above the oil separator in the Bank A camshaft cover and the induction elbow. The PCV valve prevents reverse flow into the crankcase.

Disconnection of the hose that runs between the PCV valve and the intake manifold will result in the engine becoming very unstable at idle with a tendency to stall. The OBD system will detect a fuel system fault due to the un-metered air that enters the intake manifold, please refer to the FUEL SYSTEM MONITORING  section of this document for further information.