BMW 4 Diesel: Stalling and Rough Running Issues

Hey there! I have some experience working on cars, and funny enough, I dealt with almost identical issues on my 2016 BMW 3 series diesel. Mine showed the same symptoms, rough starts, stalling, and that annoying emergency mode. I initially thought it was the sensor too, but when I took it to my workshop, they diagnosed it as a defective encoder wheel on the camshafts. The fix wasn't cheap, set me back 695 Euro, but it solved all those problems you're describing. Before I can help more specifically, could you share: Your exact engine code? Any error codes you're getting? When did these symptoms first appear? Have you had any recent work done on the engine? I've had both a 3 and 4 series, and they share quite a few components, so I might be able to offer more targeted advice once you share those details.

Hey guys! I've got the same issues with my Bimmer (126211 KM on the clock). Just had it serviced last month, and weirdly enough, these problems started showing up right after. Your post really caught my eye because it's basically identical to what I'm experiencing. That encoder wheel issue you mentioned sounds promising, definitely making a note of that. I've been dealing with those exact symptoms: rough starts, stalling, and yep, that dreaded emergency mode. My error codes are showing P0340 and P0344. I'm running the N47 engine, and honestly, it's been running like a dream until these issues popped up about two weeks ago. No other work done besides regular maintenance. Thanks for offering to help, definitely need to get this sorted before it gets worse!

Hey again! Thanks for the follow-up with those details. Those error codes actually match exactly what I saw with my car when the encoder wheel failed. When you mentioned the timing of these issues starting right after the service, it got me thinking, that's eerily similar to my situation. The P0340 and P0344 codes on the N47 engine are definitely camshaft position sensor related. But here's the thing, in my case, and quite a few others I've seen, it's rarely the sensor itself that's the culprit. That encoder wheel was the real troublemaker. Since you've got pretty much the same symptoms I had (especially that emergency mode and rough starting), I'd put money on it being the encoder wheel. What made me super suspicious in your case is that it started after the service, sometimes if the timing cover area is disturbed during maintenance, it can affect the encoder wheel alignment. Quick tip though, before you go spending big money like I did, have them check the wiring harness to the sensor. It's a way cheaper fix if that turns out to be the issue. I learned that one the hard way! Would've saved myself some cash if I'd checked that first. Let me know what you find out, I'm really curious if it's the same issue I had. Keep us posted!

Thanks so much for that detailed response! You've actually made me feel a lot better about this whole situation. I was worried I'd be looking at some major engine work, but what you're describing makes perfect sense, especially with those specific error codes matching up. I'll definitely get the wiring harness checked first, really appreciate that tip! Would've gone straight for the more expensive fix without thinking about it. I've already called my mechanic and booked it in for tomorrow morning. Asked them specifically to check both the wiring and the encoder wheel, mentioning the timing of these issues after the recent service. I'll be sure to update this thread once I get the diagnosis. Really grateful for all the help and technical knowledge you've shared. It's fantastic having someone who's been through the exact same thing! Thanks again for taking the time to help me out with this. Fingers crossed it's just the wiring harness!