PCV System: Description

The crankcase ventilation system for Audi vehicles consists of a rubber hose containing a metered orifice. Some models may contain an in-line PCV valve instead of a restricted orifice. The hose is connected to cylinder head cover at one end and the air cleaner at the other. The system is sealed and prevents crankcase vapors from reaching the atmosphere by drawing them into the air cleaner through a hose.