LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Audi >> 1981 >> 4000 5+5 >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Crankcase Ventilation Systems >> Description
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Crankcase Ventilation Systems: Description

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