If this is true, and apparently it is because VAG admitted to it, then boy oh boy is there going to be one hell of a fine levied. The TL;DR version is that VW's software for the 2.0 liter diesel engines was designed to know when it was undergoing emissions testing so that it would pass the test but in real world driving they weren't even close to emissions standards.
http://www.autonews.com/article/201...d-of-using-software-in-482000-diesels-to-skir
http://www.autonews.com/article/201...d-of-using-software-in-482000-diesels-to-skir