BMW XM Timing Chain Symptoms: Early Warning Signs

Hey there. I experienced very similar issues with my BMW X7 2019 last fall. Let me share what happened. Had identical symptoms, engine light, reduced power, metallic ticking, and terrible fuel economy. Turned out my crankshaft position sensor was failing, causing timing issues. The sensor wasn't reading the crankshaft position correctly, making the engine run rough and inefficiently. The repair involved replacing the sensor and cleaning the surrounding area since metal particles had accumulated near it. While fixing this, they also found the sensor wiring harness was slightly damaged, which needed replacement too. It's a serious issue that shouldn't be ignored, if left unchecked, it can potentially cause engine damage. The repair took about 4-5 hours at the dealership. Not the most complex fix, but definitely needs proper diagnostic equipment and expertise. Would suggest getting it checked soon, especially with those symptoms. Make sure they do a proper diagnostic scan first before jumping to conclusions.

Thanks for sharing that experience! Glad to know I'm not alone with these symptoms. Just wondering, do you remember roughly how much the whole repair set you back? Also, has everything been running smoothly since the fix, or have you noticed any other quirks?

Hey again! Happy to give you an update. Since taking my X7 to the mechanic, it's been running like a dream. The crankshaft sensor replacement sorted everything out perfectly, no more weird noises, power's back to normal, and fuel consumption is way better. Theyaged to fix the Crankshaft to camshaft reference value that was causing all the trouble. The total bill came to 340 € for the sensor replacement and labor. A bit pricey, but honestly worth every penny considering how well it's running now. Haven't had a single problem since the repair, which was about 6 months ago. The engine's smooth as silk, even on cold starts, and that annoying metallic sound is completely gone. Just make sure whoever works on yours uses proper diagnostic equipment, that's what helped identify the exact problem with mine. I'd say don't wait too long to get it fixed though, it's definitely not something you want to leave hanging. Let me know how it goes with yours!

Thanks so much for all the details! I bit the bullet and took it to a certified BMW shop yesterday. Turns out you were spot on, it was indeed the crankshaft sensor causing all the drama. The mechanic found some wiring issues too, just like in your case. The whole thing cost me a bit more, around 420 €, since they had to replace some additional wiring. But honestly, what a difference! Took it for a test drive this morning and it's running perfectly, no more weird sounds, power's back, and the engine light's finally off. Such a relief! Really appreciate your help. Would've probably stressed about this much longer if you hadn't shared your experience. Sometimes these things just need a proper diagnosis and fix from someone who knows what they're doing. Lesson learned about not putting off these repairs!