I am sure a lot of you all out there have had or are familiar with "limp mode" where your Jetta TDI just doesn't have any power. Frankly when I first experience it, I was very concerned, read a lot from the forums, and was sure it was the TurboCharger. I actually ordered one, and was in the process of taking the old one off, when I found the REAL problem. There is an expandable pipe that goes between the EGR cooler and the exhaust manifold/turbocharger. When - in the process of disassembly - I took it off, it came off in two pieces. Since it is a VW DEALER only part, I went to the local dealer, picked up the connector pipe, and installed it. I decided that this was too good an opportunity to pass up, so I put everything all back together, and to my delight it worked like a champ. For the price of the connector pipe ($95), I saved over $600 by returning the unneeded Turbocharger. It may not work for you, but it certainly worked for me and is a good first thing to check. Symptoms are idential, so I would recommend that you check this out first.