BMW M3 Camshaft Sensor Woes: Help and Advice Needed

Hey there! I had nearly identical issues with my 2015 BMW M4. The symptoms you're describing match exactly what I experienced, rough starts, misfiring, and that annoying limp mode with reduced power. Initially thought it was the sensor itself, but when I brought it in, turned out the wiring harness connecting to the camshaft sensor was damaged. Some of the pins were corroded and the connector wasn't making proper contact. Had it fixed at the workshop last month. The mechanic showed me how the old wiring had wear marks and corrosion inside the connector housing. They replaced the entire harness section and sensor as a precaution. It wasn't a major repair in terms of engine work, but definitely not something to ignore since it can lead to more serious issues if left unchecked. Since the fix, the car's been running perfectly, no more misfires or power issues. Just make sure whoever works on it uses genuine BMW parts for the replacement. The sensor and wiring are pretty critical for proper engine timing. Hope this helps!

Thanks for sharing your experience! That's really helpful info about the wiring harness. Quick question, do you remember roughly how much the repair set you back? And has everything stayed running smooth since then, or have you noticed any other quirks pop up? Just wanna know what I might be in for with my M3.

Hey again! Glad I could help! Just wanted to update you, since seeing the mechanic last month for that camshaft sensor issue, my M4's been running like a dream. The final bill came to 95 € for fixing the cable connection, which honestly wasn't as bad as I'd feared. The mechanic found it was just a faulty connector that needed sorting out rather than the whole sensor being dead. And to answer your question, absolutely zero issues since the repair. No more of those annoying misfires or power drops that were driving me crazy before. Starting up is smooth as butter now, and the engine's got all its power back. Definitely worth getting it sorted properly rather than letting it drag on. Looking back, I was probably stressing more than I needed to about it. These things happen with performance cars sometimes, but at least it was a relatively simple fix in the end. Let me know how yours turns out!

Thanks for all the details! I actually just got back from the mechanic today. Turns out my issue was pretty similar to yours, faulty wiring was the culprit. The repair was quick and painless, and they even showed me the worn-out parts they replaced. The best part? My M3's running like new again. No more struggling to start, no misfires, and the power's fully back. The mechanic I found was really thorough and took the time to explain everything. They even cleaned up some other minor issues they spotted while they were at it. Total cost was a bit higher than yours since they replaced both the sensor and wiring harness, but honestly, it's worth every penny to have the car running properly again. Really glad I didn't put this off any longer. Thanks again for sharing your experience, it definitely helped me know what to expect!