BMW XM Exhaust Gets Louder, Flap Control Failure?

Had the same problem with my 2020 BMW M5 Competition last month. The exhaust flap actuator failed completely, causing that loud cold start and uncontrollable flap behavior. Got the error code too. Found a garage specializing in BMW M cars, they diagnosed a seized actuator motor and corroded wiring harness. The mechanic showed me how the flap was stuck in the open position, explaining why it was so loud. They replaced both the actuator and harness. Not a super serious issue for engine health, but definitely needs fixing since it affects emissions control and could lead to inspection failure. The repair took about 4 hours. Worth getting it checked by someone who knows these performance exhausts, the systems are quite complex on M cars. Working perfectly now, flap responds normally and sound levels are back to standard. Just make sure to find a shop that regularly works on M models.

Hey, thanks for sharing your experience! That's exactly what's happening with my XM. Gives me some peace of mind knowing it's likely just the actuator and wiring. Good to hear it's not engine-related at least. Quick question, do you remember roughly how much you ended up paying for the whole repair? Also, has everything stayed working properly since the fix, or have you noticed any other quirks popping up?

Hey! Glad to help update you on my M5 situation. The repair was totally worth it, cost me 190 € and everything's been running perfectly since they fixed it. The exhaust flaps are working exactly as they should now, no more of that annoying constant loud noise or error messages. It's been about 6 weeks since the repair, and I haven't had a single issue pop up. The cold starts are back to normal volume, and I can control the flaps again through all the different drive modes. Honestly, it's like having a new car again, you forget how annoying these little problems can be until they're fixed! Trust me, once you get it sorted, you'll be much happier. The XM's exhaust system is pretty similar to the M5's, so you should be looking at comparable repair costs. Just make sure whoever works on it knows their way around M cars like we discussed before.

Thanks for the detailed follow-up! Just wanted to update you guys too, got my XM fixed today. Finally found a good mechanic through a and you were spot on about everything. They diagnosed the same issues, faulty actuator and some corroded wiring. Repair bill came to about 200 € total, pretty close to what you paid. The mechanic was super helpful and even showed me what was causing the problem. Fixed it in about 3 hours, and wow, what a difference! The car sounds perfect now, those awful cold start noises are gone, and I've got full control of the exhaust flaps again. Best part? The mechanic actually took the time to explain everything and even cleaned up some other minor issues while they were at it. Such a relief to find someone who knows what they're doing with these cars. Thanks again for pushing me to get it checked out, should've done this weeks ago!