PCV and Vacuum
The following parts listed below are for MK5 Jetta's for 2006, 2007 and 2008.5. The 2.0T FSI engine has been known to have a few issues with the PCV system. TIn this category you will find the PCV valves as well as other vacuum system parts for the MK5 Jetta with a 2.0T FSI engine. It is important to note that the FSI engine uses 2 different PCV Valves which are not interchangeable. You may need to pull the part number off of your old PCV valve (found on the bottom of the valve) to ensure you get the correct one. '
Take a look here for more info about common FSI PCV and Vacuum Problems