BMW 3 Diesel DPF Nightmare: Failed Regen and Smoke Issues

Hey there! I had similar problems with my 2015 BMW 5 diesel. I've got some experience working on cars, mainly basic maintenance stuff. My symptoms matched yours exactly, DPF warnings, sluggish performance, and that annoying smoke. Turned out it was indeed the exhaust back pressure sensor. My local workshop diagnosed it, and replacing the sensor solved everything, cost me 245 Euro. The car's been running perfectly since then. But before jumping to conclusions, could you share: Current mileage? Any other warning lights? How often do you drive long distances? This info would help confirm if you're dealing with the same issue I had. The symptoms really sound identical, but it's best to be sure.

Thanks for your feedback! My mileage is 156583 KM and I just had the service done last month. No other warning lights at the moment, just the DPF ones you mentioned. Really helpful to hear about your experience with the sensor, gives me more confidence that's the likely culprit. I do mostly short trips, probably only one longer drive per week, which probably hasn't helped the DPF situation. Might try a good motorway run before taking it to the workshop, but sounds like I should get that sensor checked out regardless.

Hey again! Thanks for those extra details, yeah, those short trips are definitely not doing your DPF any favors. Same thing happened with mine before the sensor issue. Just wanted to add something based on my experience, before you get the sensor replaced, try doing what worked temporarily for me: take it for a proper long drive (at least 30 minutes) at steady speeds. In my case, it helped clear things up briefly, but the problem came back after a few days because the sensor was actually faulty. The mileage you mentioned is pretty close to when mine started acting up too. Given all these matching symptoms, I'm even more convinced you're dealing with the same sensor issue I had. One thing though, when my workshop did the repair, they also cleaned the DPF since it had gotten pretty clogged from all those short trips. Might be worth asking about that too when you take it in. The total job took about 3 hours, but it was totally worth it. Haven't had a single DPF warning since then, and the smoke issue completely disappeared. Let us know how it goes, curious to see if it's the same fix as mine!

Thanks so much for all the detailed advice! Really appreciate you sharing your experience, especially about the DPF cleaning. I've actually booked it in for next week at the workshop, and I'll definitely mention both the sensor replacement and DPF cleaning to them. Going to try that 30-minute drive you suggested this weekend, nothing to lose, right? Even if it's temporary, it might help until the repair. Really good to know the repair fixed all your issues completely. It's such a relief to hear from someone who's dealt with exactly the same problem and got it sorted. The fact that your mileage was similar when it happened makes me feel better about the whole thing too. Will update the thread once it's fixed to help others who might run into the same issue. Thanks again for taking the time to help me out with this!