BMW 4 Series DPF Warning: Black Smoke & Engine Troubles

Hey there! I had nearly identical issues with my 2016 BMW 3 Series diesel last year. The symptoms were spot on, DPF light, black smoke, and rough running. The exhaust back pressure sensor was indeed faulty on mine. Got it checked at a garage, and they confirmed the sensor was giving incorrect readings, causing the DPF system to malfunction. The repair involved replacing the sensor and cleaning the DPF. It wasn't a major repair, but it's definitely something you want to address soon to prevent potential damage to the DPF system. The job took about 3 hours. These sensors are pretty sensitive components, and when they fail, they can really mess with the engine's performance. Mine's been running perfectly since the fix, no more black smoke, engine's smooth, and passed emissions with flying colors. Don't put it off too long, a faulty sensor can lead to bigger issues if left unchecked. Best of luck!

Thanks for sharing your experience! That's really helpful as it sounds exactly like what I'm dealing with. Good to hear it was sorted without any major drama. Just wondering, do you remember roughly how much you ended up paying for the whole job? Also, has everything stayed running smoothly since the repair, or have you had any other issues pop up?

Hey again! Happy to give you an update! Yeah, I had the work done and it cost me 245 € to fix the faulty exhaust back pressure sensor. Money well spent if you ask me, the car's been running like a dream ever since. It's been about a year now, and I haven't had a single issue pop up related to the DPF or anything else. No more black smoke, engine's purring like a kitten, and she's passing emissions tests without breaking a sweat. I remember being worried like you about potential bigger problems, but honestly, once they replaced that sensor, everything fell right back into place. If you're dealing with the same symptoms, I'd definitely recommend getting it sorted sooner rather than later. The peace of mind alone is worth it, and you'll notice the difference in how the car drives straight away. Let me know if you need any other info about it, happy to help!

Thanks so much for all the info! I actually went ahead and got it fixed yesterday. Found a reputable mechanic through a and you were spot on, it was the exhaust back pressure sensor. Cost me a bit more at 295 €, but the service was fantastic. The mechanic walked me through everything they did, showing me the old sensor and explaining how it was affecting the engine. They had it done in about 4 hours, which included a thorough DPF cleaning as well. You wouldn't believe the difference, no more black smoke, the engine's running smooth as silk, and that annoying warning light is finally gone! Really glad I didn't put it off any longer. The mechanic mentioned the same thing about preventing bigger issues down the line. They also gave the rest of the exhaust system a once-over and everything else looked good. Thanks again for helping me make the decision to get it sorted. It's such a relief to have it running properly again!