Concern about Audi A4 Diesel: Suspected EGR valve problems and workshop experience wanted

Hi, I had a similar situation to yours with my Audi A6 from 2011. In my case, it was actually the EGR valve that was defective and jammed. Your symptoms sound very similar to mine back then. The vehicle ran rough, shuddered at idle and gave off these strange smells. The check engine light also came on. My mechanic replaced the EGR valve and after that the car ran like clockwork again. It was definitely a serious problem that needed to be fixed to prevent further damage. I would advise you not to wait too long and take the car to a garage. It definitely sounds like a problem with the EGR valve. Good luck!

(Translated from German)

Hi, thanks for the quick reply! Your experience sounds exactly like mine now with my A4. It really is a nightmare the way it's behaving at the moment. Could you remember how much it cost you to change that EGR valve? Also, have you had any other problems since then, or has your Audi been running smoothly since then? Hopefully I won't have any more issues... Best regards!

(Translated from German)

Hello, no problem, I'm happy to help! So, my mechanic charged me around €355 to replace the EGR valve. It was a tidy sum, but it was definitely worth it. Since then, the functional fault in the EGR valve has been rectified and my Audi runs without any problems. It was a one-off investment, so to speak, to avoid major future damage. Now everything is back to normal and my car runs like on the first day. I hope it works just as well for you and that no further problems occur! Best regards!

(Translated from German)

Hi, Wow, that sounds like a lot of money, but as you say, it seems worth it. I'm definitely going to take my Audi to the garage now and have the EGR valve replaced. I really hope the replacement will solve all the problems and I can drive smoothly again. Thank you so much for your help and advice, it has been really encouraging during this stressful time! All the best for you and your Audi! Bye bye!

(Translated from German)

Hello, my car is a 2023 Audi A4 with 78,000 km. The engine light came on, and when I connected an OBD device, it gave a P0401 error code, which indicated an EGR system malfunction. I took it to a repair shop, and they replaced the entire EGR system, costing 500€. However, the engine light came back on, and the OBD still shows the P0401 error. I don't know what could be wrong. Some sources say that the MAF and MAP sensors need to be cleaned. The error light comes on after only 25 km of driving. At this rate, I'm going to sell the car!!! Thanks

(Translated from Turkish)

Hello, my 2013 Audi A4 (78,000 km) was giving me a P0401 EGR error code. A repair shop replaced the entire EGR for 500€, but after driving 25km, the light came on again. Checking with an OBD device, the problem is still the same, P0401. Some people told me I need to clean the MAF and MAP sensors. What could the problem be?

(Translated from Turkish)

Start by checking for any vacuum leaks in the EGR system, as these can cause the P0401 code to persist even after replacing the EGR valve. Inspect the hoses and connections for any signs of wear or damage. If you find any issues, repairing them might resolve the problem. Let me know how it goes or if you have any further questions!

Check for any vacuum leaks in the EGR system, as these can cause the P0401 code to persist even after replacing the EGR valve. Inspect the hoses and connections for any signs of wear or damage. If you find any issues, repairing them might resolve the problem. Let me know how it goes or if you have any further questions!