Audi Q7 EGR Issues Causing Multiple Drive Problems

I dealt with almost identical issues on my 2021 Audi Q5. The symptoms you describe match perfectly with what I encountered, especially the power loss and check engine light, which were the first signs something was wrong. The recirculation system problems led to failed emissions tests, and the workshop confirmed a faulty EGR valve was the culprit. They performed a thorough diagnostic check which showed the valve was stuck partially open, causing irregular exhaust gas flow. The repair cost me 355 Euro total, including parts and labor. After replacement, all symptoms disappeared and the catalytic converter readings returned to normal. Yes, I needed a new emissions test afterward to clear the system and verify everything was working correctly. Before suggesting specific next steps, could you share: Current mileage on your Q7, Any recent service history related to emissions components, Complete error codes from the check engine light, Whether the issue occurs more during cold starts or when the engine is warm This information would help determine if your case is similar and whether the EGR valve is definitely the root cause.

Thanks for sharing your experience. My Q7 has 156670 KM and just had its annual service last month where they found nothing unusual in the vehicle emissions system. I pulled the error codes yesterday which show P0401 (insufficient EGR flow) and P0402 (excessive EGR flow). The issues definitely get worse when the engine is warm, especially the smoke and power loss during acceleration. Based on your repair cost details, this seems like a reasonable fix to pursue. The automotive repair shop I contacted wants to do a complete diagnostic first rather than just replacing the EGR valve. Did your emissions test immediately after the repair show any lingering issues that needed additional work?

From my experience with the Q5 repair, going for a full diagnostic first is actually the smart move, even though I was quite certain about the EGR valve being the issue. The rough idle and vehicle emissions problems I experienced showed similar patterns to yours, worse with a warm engine. Those error codes you mentioned are exactly what my system showed. The combination of P0401 and P0402 typically confirms an EGR valve that is malfunctioning rather than just being clogged. In my case, the check engine light stayed on even after cleaning attempts, which ultimately proved it needed full replacement. The post-repair emissions test was clean on the first try, with no additional work needed. However, the repair shop did have to clear all the system codes and run through a complete drive cycle to ensure the engine management system properly recognized the new valve. The whole process, including the final emissions test, took about 48 hours to complete. Quick tip from my experience: while they have the system open, have them check the EGR cooler too. On my Q5, it was starting to show early signs of wear, though it wasnt critical yet. Better to inspect it while they are already working in that area.

The information you shared about the Q5 repair is really valuable, especially regarding system codes and test cycles. Since our symptoms are nearly identical, I feel more confident about moving forward with the diagnostic process. Going to schedule the full inspection at the shop today. The rough idle and vehicle emissions issues getting worse with engine temperature match your experience exactly. Makes sense about checking the EGR cooler while they are in there, will definitely request that. One last question about those post-repair drive cycles: did you need to follow any specific driving patterns during the 48-hour period to ensure proper system recognition of the new EGR valve? Just want to make sure I handle everything correctly to avoid any further check engine warnings or failed emissions tests. Our situations seem so similar that I expect my repair costs will be in the same 355 Euro range. Really appreciate you walking me through your experience, it has helped clarify what to expect from the whole process.