The PCV provides a one way exit for gasses built up in the crankcase. Over time, contamination might cause reduced air flow and cracks can occur in the housing. If your car is experiencing a loss of boost pressure or a decrease in performance with a rough idle, this valve might to be blame.. Replace your faulty PCV valve to keep your engine running at full potential.
* This part is designed for the TSI engine only. This can easily be found on the engine cover of your 2.0T VW/Audi. It will clearly be stamped TSI or TFSI.