Hi, I had a similar problem with my 2013 Audi A4 diesel, I only have some experience with cars but it sounds like a faulty diesel particulate filter to me too. At my garage they replaced the filter, it cost me about 1550 euros. It was a bit expensive, but apparently the diesel particulate was defective due to high mileage. Could you also tell me how many kilometers your TT has already run? That could help solve the problem. Hope this helps you!

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Hey, thanks for the quick reply! My TT already has 224678 km on the clock. The last service was only recently, but the problem was already there. So, it could really be the diesel particulate filter. I hope this helps to narrow down the problem. Your repair costs don't sound too encouraging though, I must say! I really hope it won't be that expensive. Thanks again!

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No problem, always welcome! With the number of kilometers and the symptoms already present, I would strongly suspect that it is the diesel particulate filter. With so many kilometers, the filter can already be heavily loaded. And yes, I know the repair costs are really high, but I had peace of mind afterwards. Maybe you can get a second opinion from another garage to reduce the costs a bit. Even if it's going to be expensive, I wouldn't put it off, otherwise it could get even more expensive. Good luck, hopefully you'll get it sorted quickly and cheaply!

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Thanks, Dude! Yeah, I'll probably go to the nearest garage and get a second opinion before I make a decision. In any case, I'll tackle the problem now before it gets worse. Thanks for the tips and help, that was really helpful!

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