Hey, I experienced something similar with my 2008 Audi A3 TDI. The same smell, the same smoke and the same drop in performance. It was actually the diesel particulate filter that was too heavily loaded. The DPF regeneration was simply no longer able to cope. So off to the workshop. That was a lot of work, though. They had to remove the entire diesel particulate filter and fit a new one. It was pretty serious, not just a simple fix. But after that, my car ran like clockwork again and the engine warning light went out. I hope that helps you.

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Hey, thanks for the quick reply. Your experience sounds really similar to what I'm going through with my A2 right now. Your mechanic seems to have done a really good job. Do you remember roughly how much it cost? And have you had any other problems since then? Hopefully my car will hold up as well as yours after the repair.

(Translated from German)

Hey, I'm glad my experience is helping you. Well, fixing the diesel particulate filter has already cost me quite a bit. I had to put around €1550 on the table to fix the diesel particulate due to the high mileage. It's a lot of money, but it was definitely worth it because my car has been running like clockwork ever since. And luckily I haven't had any further problems with the filter since then. I just hope that your A2 comes through as well as my A3 did after the repair. Keep your fingers crossed, buddy!

(Translated from German)

Wow, that's pretty expensive, but if it helps, then no price is too high for me. I can't really afford such repairs, but what won't you do for your beloved car, right? At least I hope it will get rid of these annoying problems once and for all. Your experience gives me courage. Many thanks for the help and the encouraging words. I'll try my luck with my mechanic and hope for the best.

(Translated from German)