Took my post-settlement 2011 Sportwagen TDI to dealer as a result of these symptoms and because I've lost an average of 7-10 mpg per tank. It had been going on for about two months. They kept it three days and found nothing. Told me it was probably a regen. There is absolutely no soot or anything else that would indicate a regen. Still happening. I know plenty o people have experienced this, but have any of you experienced it in this way? Take to a new dealer? How do I get this diagnosed? Still under warranty.