Your assumption could well be correct. I've had similar experiences with my 2011 Audi A4 diesel and yes, it was the EGR valve too. I would say I have some experience with cars, but I'm not a professional. I had the EGR valve replaced at my garage. They ran a fault diagnosis with the diagnostic tool, which revealed that it was actually the EGR valve that was faulty and stuck. This ended up costing me about 355 euros, but was unavoidable. It would be helpful to know how many kilometers your Audi A3 has run and whether you have made any changes to your vehicle? With a bit more information, I might be able to help in more detail. But in any case, I would advise you to have it checked at a garage.

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Hey, thanks for the quick reply and the helpful information. Well, my A3 has already done 250123 km and the last service was a few months ago. There was no mention of any major problems. That's why I was really surprised. I had the feeling that the performance had deteriorated recently, but I didn't think anything more of it. I haven't made any major changes so far and actually drive the car as I bought it. The cost is obviously stupid, but if it helps, I'll probably have to have it done. I'll definitely take it to the garage and have it checked. I'll let you know what comes of it. Thanks again for the tips!

(Translated from German)

Hey, no problem! With the mileage on your A3, it could well be that the EGR valve is actually causing problems. Mine had a similar number of kilometers on it when this happened to me. It's always wise to get things like this checked because it could develop into bigger, more expensive problems over time. I can understand that the cost is unpleasant, but ultimately it's best to get the car running smoothly again and avoid potentially worse damage. It would be great if you could keep us updated after you've been to the garage. It might help others who have the same problem. Fingers crossed that it's nothing worse! Feel free to post if you have any more questions or need further advice. Have a safe journey!

(Translated from German)

Great, thanks for the support! You're right, it's definitely better to check it now than have major problems later. I will have the EGR valve checked at the garage and get back to you with the results. Your information was very helpful, I feel better prepared now. Many thanks for the good wishes and if I have any more questions, I'll be sure to get in touch! See you then, and have a safe journey!

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