BMW X3 Diesel: DPF Issues Causing Power Loss & Smoke?

Hey there! I have some experience working on cars and had a very similar issue with my 2019 BMW X5 diesel last year. The symptoms you're describing sound exactly like what I dealt with, my 530d had the same problems too. My warning light came on while driving, and I noticed the same reduced power and smoke. Took it to my trusted workshop, and it turned out to be a faulty exhaust back pressure sensor. The repair, including parts and labor, cost me around 245 Euro. The mechanic said these sensors commonly fail on diesel BMWs. Before I can give more specific advice, could you share: How many miles/kilometers on your X3? Have you noticed any other warning messages? Did the issue start suddenly or gradually? Have you had any recent DPF regeneration cycles? Let me know these details, and I might be able to share some more relevant insights from my experience.

Thanks for your detailed reply! My X3 has 186862 KM and just had its service last month. The issue started quite suddenly during my morning drive. No previous warning messages before this. Honestly, I'm not sure about the DPF regeneration cycles, I haven't been paying attention to that. Your experience with the exhaust pressure sensor sounds similar to what I'm experiencing. Did changing the sensor fix all your symptoms immediately? Just wondering if I should expect any other related issues to pop up. Thanks for offering to help!

Hey again! Yes, replacing the exhaust pressure sensor on my X5 fixed all those symptoms right away. It was like night and day, the warning lights disappeared, power came back, and no more smoke or weird smells. That's interesting that yours started suddenly too, exactly like mine. And your mileage is pretty close to what mine had when the issue occurred (I was around 175000 KM). Since you just had service done last month, I'd check if they did anything related to the exhaust system, as sometimes these sensors can act up after maintenance work. In my case, I didn't have any related issues pop up afterward. But I did start paying more attention to my driving style to help the DPF regeneration cycles, like avoiding too many short trips and giving it a good run on higher revs occasionally. Been about 14 months since the repair, and everything's still running perfectly. One thing I learned from my experience, don't wait too long to get it checked out. When I first noticed the symptoms, I kept driving for a few days hoping it would sort itself out. Not my smartest move! Better to get it looked at sooner rather than later. Let me know how it goes if you get it checked out. Always curious to hear if others have the same fix work for them!

Thanks so much for sharing your experience, it's really helpful to hear from someone who's been through the exact same thing! I'll definitely take your advice and get it checked out right away rather than waiting. Actually booked it in for tomorrow morning at my local workshop. It's reassuring to know that fixing the sensor solved all your problems completely, and I'm hoping for the same outcome. Really appreciate the tip about the driving style too, hadn't thought about how short trips might affect the DPF. Makes total sense why my mechanic always mentions giving it a good run on the highway occasionally. I'll definitely keep a closer eye on that after it's fixed. I'll try to remember to update you after the workshop looks at it. Thanks again for all the detailed info, it's made me feel a lot more confident about dealing with this issue!