BMW 6 Series MAF Issues, Multiple Engine Problems

Hey there! I've got some experience with BMWs (some experience, worked on 3 cars before). I actually had a similar issue with my 2017 BMW 4 Series last year. The symptoms were exactly like yours, rough idle, poor acceleration, and that annoying check engine light. Got it diagnosed, and yep, it was the mass air flow sensor. Took it to my trusted mechanic, and the whole thing, including parts and labor, cost me about 365 Euro. Before I can give you more specific advice, could you share: Have you scanned for error codes? How many miles/kilometers on your 6 Series? Any other recent repairs or maintenance? For reference, I've also owned a BMW 3 Series, and these sensors can be quite finicky across the lineup. Let me know those details, and I can probably help you better with your specific case.

Thanks for your input! Currently at 78842 KM and just had the service done last month. I did scan for codes using my 's diagnostic tool and got P0171 and P0174, which point towards a lean fuel mixture. You're right about the repair costs being in that range, I've been calling around and getting similar quotes. Interesting that you had the same symptoms with your 4 Series. Did cleaning the sensor first help at all, or did you have to go straight for replacement? I'm tempted to try cleaning it myself before spending on a new one, but don't want to make things worse.

Hey again! Thanks for those details about your BMW. Yeah, I actually tried cleaning my MAF sensor first when I had those exact same codes (P0171 and P0174) on my 4 Series. Used proper MAF sensor cleaner and everything, but honestly, it only helped for about a week before the symptoms came back. After that temporary fix failed, I just bit the bullet and went for the replacement. Looking back, I probably should've just replaced it straight away, would've saved me some headache and time. The cleaning supplies cost me around 20 bucks anyway, so not a huge saving in the end. Since your mileage is pretty similar to what mine was when it failed (I was at about 75,000 km), and you're getting the same codes, I'm even more convinced it's the same issue. Just a heads up though, make sure you get a quality OEM sensor. I made the mistake of trying an aftermarket one first (trying to save some cash), but it didn't work right and I ended up having to get the BMW original part anyway. One more thing, after the replacement, it took my car about 50-100 km to fully adjust to the new sensor and run smoothly again. So don't panic if it's not perfect right away. Would love to hear what you decide to do and how it works out!

Thanks so much for the detailed follow-up! You've honestly saved me from making the same mistakes. I was seriously considering going the aftermarket route to save money, but after hearing your experience, I'll definitely stick with the OEM part. I think I'll skip the cleaning attempt too, sounds like it would just be wasting time and money. I've already scheduled an appointment with my mechanic for next week. They quoted me 370 Euro for the OEM part and labor, which seems fair based on what you paid. Really appreciate the heads up about the adjustment period after replacement. That's super helpful to know, I probably would've freaked out if it wasn't running perfectly right away! I'll keep you posted on how everything turns out after the repair. Thanks again for all your help, it's been incredibly useful having someone who's been through the exact same thing!