BMW X6 Engine Stalling and Power Loss Mystery Needs Solving

Hey there! I had nearly identical issues with my 2014 BMW X5 35i last year. The symptoms were spot on, rough idle, unusual power loss, and that annoying check engine light. Turned out you're right about the crankcase ventilation system being the culprit. In my case, the PCV valve was completely clogged, and the diaphragm was torn. I ended up finding a good BMW specialist who really knew what they were doing. The fix involved replacing the entire PCV valve assembly and cleaning out the intake manifold, which had gotten gunked up due to the failing PCV system. It wasn't a quick fix, took them about half a day to complete everything. This is actually a pretty serious issue because a failed PCV system can cause oil consumption problems and eventually damage your engine if left unchecked. My advice would be to get it checked soon, those symptoms won't go away on their own, and they'll likely get worse over time. Since you've had a bad experience before, I'd suggest finding a shop that specializes in BMWs. The repair isn't overly complex, but it does require someone who knows these engines well.

Thanks for sharing your experience! That's super helpful, and it sounds exactly like what I'm dealing with. You're making me feel better about my initial diagnosis. If you don't mind me asking, what did you end up paying for the whole repair? Also, has everything been running smoothly since then, or have you noticed any other issues pop up? Would appreciate the heads up if there's anything else I should watch out for.

Hey again! Happy to update you! The repair came to 360 Euro, and honestly, it was worth every penny. Everything's been running like a dream since I got it fixed, that power lag and rough idle are completely gone. The check engine light hasn't shown its face again either! Just had the work done last month, and the difference is like night and day. My mechanic really knew their stuff about these engines. The whole PCV system needed replacement, but once they sorted that out, the car's performance went right back to normal. You know what's funny? I was worried like you at first, thinking it might be something way more serious (and expensive!). But nope, just that pesky crankcase ventilation valve causing all the drama. Haven't noticed any other issues since the fix, the car's running as smooth as silk. Just make sure you find someone who really knows BMWs. Mine cleared out the intake manifold while they were at it, which probably helped prevent any future problems. Trust me, once you get it sorted, you'll notice the difference straight away! Let me know how it goes with yours, always curious to hear how these repairs work out for others.

Thanks so much for all the details! I actually just got back from getting it fixed, and you were absolutely right. Found a really good BMW specialist through a and they diagnosed the same issue, clogged PCV valve and gunked-up intake manifold. The repair cost was a bit higher at 450 Euro, but they did a thorough job. Had to leave the car there for most of the day, but wow, what a difference! The engine's running super smooth now, no more power drops, and that annoying check engine light is finally off. The mechanic also showed me the old parts, they were in pretty rough shape! Funny thing is, they mentioned I caught it just in time before it could cause any serious damage. Really glad I didn't put it off any longer. The new mechanic was great too, explained everything clearly and didn't try to upsell me on unnecessary stuff like my last one did. Thanks again for pushing me to get it checked out. You really saved me from what could've been a much bigger headache down the road!