BHB PCV Valve Engine Crankcase Vent Valve Compatible with VW & Audi Jetta/Passat/Golf/Bettle/A3/A4/A5/A6/A7/Q3/Q7 1.8 2.0 06K103495 Oil Separator. PCV valves used for too long can form sludge that clogs the internal surfaces of the engine and causes engine wear.