Audi Q7 Engine Troubles: MAF Sensor Warning Signs

Had almost the same issue with my Audi A6 3.0 TFSI from 2013. These symptoms match perfectly with what I experienced, performance decline, engine stalling at idle and the check engine light coming on. After some basic checks of the air filter and intake system, my trusted workshop confirmed it was indeed a faulty mass air flow sensor. The repair took about 2 hours and cost me 365 Euro including parts and labor. Since the fix, fuel consumption returned to normal and the engine runs smoothly again. No more stalling or performance issues. With some experience working on similar engines, I would suggest checking a few things before replacing the MAF sensor: Clean the air filter housing for debris, Inspect for loose connections around the mass air flow sensor, Look for vacuum leaks in the intake system To properly diagnose your Q7, could you share: Current mileage, When was the last air filter change, Any recent engine work done, Are there any other warning lights besides check engine, Did these symptoms appear gradually or suddenly This information would help determine if your case is similar and if there might be related issues to address.

Latest service was at 159000 KM with an air filter change, now at 162099 KM. The air filter check and intake inspection suggestions make sense. My symptoms did come on gradually over about 2 weeks. No additional warning lights beyond the check engine light. The fuel economy has gotten significantly worse, now using about 20% more fuel than normal. The engine stalling happens mostly when the engine is warm, especially at traffic lights. At this mileage, I understand these components can start failing. A full diagnostic scan might be worthwhile before replacing parts, since the MAF sensor is somewhat expensive. Looking to schedule a workshop visit next week to confirm the issue.

Thanks for the additional details. Your situation sounds even more similar to what I experienced with my A6. The gradual onset of symptoms over weeks matches exactly how my MAF sensor failure progressed, especially the warm engine stalling at idle. When my car hit 160000 KM, the sensor failure manifested in stages, first with minor performance decline, then progressing to the stalling and smoke issues. The 20% increase in fuel consumption you mentioned mirrors my experience precisely. A quick check that helped confirm my MAF sensor issue before replacement: the engine ran noticeably smoother with the sensor unplugged, though at reduced power. This is because the ECU defaults to preset values rather than using potentially incorrect MAF readings. The diagnostic scan on my A6 showed fault code P0101, which specifically indicated MAF sensor problems. Given your identical symptoms and similar mileage, getting that scan is definitely the right next step. Just ensure the workshop checks for vacuum leaks during diagnostics, while my issue was the MAF sensor, these can cause similar symptoms and are worth ruling out. The full diagnostic at my workshop cost 85 Euro, which was worth it for the certainty before replacing the sensor.

Thanks for all the suggestions and sharing your experience. After reviewing the symptoms you described with your A6, I feel more confident that the MAF sensor might be the culprit in my Q7. The matching pattern of gradual performance decline and fuel economy issues at similar mileage is quite telling. I appreciate the tip about checking how the engine runs with the sensor unplugged, that could be a useful test before committing to the replacement. I will definitely get that diagnostic scan done first to confirm the fault code. The 85 Euro diagnostic fee seems reasonable to ensure we target the right problem. Will also have them check for vacuum leaks in the air intake system during the inspection, as suggested. Your repair cost of 365 Euro helps set my expectations for the budget. Given the symptoms keep getting worse and the significant impact on fuel economy, I would rather address this sooner than risk further issues. Will schedule that workshop visit and update once I have more information about the actual diagnosis.