BMW X3 Engine Troubles: Rough Running and Limp Mode Issues

Hey there! I had a pretty similar issue with my 2016 BMW X5 last year. The symptoms you're describing sound exactly like what I dealt with, rough running, jerking, and limp mode. Mine turned out to be a leaky exhaust system that was throwing off all the sensor readings. Took it to my regular workshop, and they found cracks where the manifold connects to the exhaust pipe. Set me back about 265 Euro for the repair, but it fixed all those issues instantly. No more check engine light or performance problems since then. Before I share more specific details, could you tell me your current mileage and if you're getting any specific error codes? Also, have you noticed any unusual exhaust sounds or smells? This would help me give you more targeted advice based on my experience with BMW engines. BTW, from your symptoms, definitely get it checked soon before it causes more problems. These issues tend to get worse pretty quickly with BMW's.

Thanks for the detailed response! I'm at 38696 KM and just had my service done recently. I haven't noticed any weird exhaust sounds, but I'm getting P0300 and P0303 codes. My car runs fine when cold but gets worse as it warms up. Sounds different from your exhaust issue though, I'm starting to suspect it might be ignition coils or injectors. Was the exhaust repair the only thing you needed to do to fix all those symptoms completely?

Hey again! Just want to follow up on this. Yeah, in my case the exhaust leak was the main culprit, but after reading your codes (P0300 and P0303) and symptoms, you're definitely dealing with something different than what I had. Those codes typically point to misfires, and the fact it gets worse when warm is really telling. Actually, after you mentioned it, I remembered I had a similar misfire issue about 6 months before my exhaust problems. Had to replace two ignition coils and one spark plug that were shot. The symptoms were exactly what you're describing, rough running when warm and jerking during acceleration. Cost me around 200 for parts and labor, way cheaper than I expected. Quick tip from my experience, if you're getting a cylinder 3 misfire (P0303), you might want to swap the coil from cylinder 3 with another cylinder and see if the misfire follows. That's what my mechanic did to confirm it was the coil. If the misfire moves to the other cylinder, you've found your culprit. These BMWs can be finicky with ignition components, but at least it's a pretty straightforward fix. Let me know what you find out, I'm curious if we ended up having the same root cause!

Thanks so much for the super helpful follow-up! That coil-swapping diagnostic tip is brilliant, I'll definitely try that before taking it to the shop. It makes total sense that it could be ignition coils, especially since the symptoms match what you experienced. Really relieved to hear it might be something relatively simple and not too expensive to fix. I'll grab the error codes again after swapping the coils around and let you know what I find. The fact that your car's been running great after replacing the coils and spark plugs is really encouraging. These BMW engines are amazing when everything's working right, but yeah, they can definitely be particular about maintenance. Really appreciate you taking the time to share your experience, it's given me a solid starting point for getting this sorted out! Hopefully it'll be just as straightforward a fix as yours was.