BMW X5 3.0 Power Loss: Turbo Boost Issues?

Hey there! I had a very similar issue with my 2014 BMW X3 3.0i last year. I have some experience working on cars, mainly basic maintenance and repairs. The symptoms you're describing sound exactly like what I experienced. My X3 was losing power, especially during acceleration, and fuel consumption went through the roof. After taking it to my regular workshop, they diagnosed a faulty vacuum switching valve, it was causing inconsistent boost pressure control. The fix wasn't too complex, but definitely needed professional tools. Total cost was around 140 Euro including parts and labor. Since the repair, my car runs like new again, no more power loss or jerky acceleration. Can you share if you're getting any specific error codes? Also, when exactly do you notice the power loss the most, during cold starts or after the engine is warmed up? This info would help compare our situations better. PS: If it's the same issue, you're lucky, it's a relatively straightforward fix compared to other boost-related problems these engines can have.

Thanks for sharing your experience! Just had my service done last month at 119347 KM, and this issue started popping up about a week ago. The power loss is most noticeable when the engine's warm, especially when trying to overtake on highways. I'm getting error code P0299, which does point to boost pressure problems like you mentioned. Your repair cost sounds way more reasonable than what I was fearing. Was thinking it might be something more serious like a turbo issue. Will definitely get the vacuum switching valve checked first. Did they keep your car for long during the repair?

Hey again! Yeah, that P0299 code is exactly what I had too! When you mentioned the symptoms being worse after the engine warms up, it really confirms my suspicion about the vacuum switching valve. In my case, they only needed the car for about 3-4 hours to complete the repair. Actually, I was also worried about turbo problems initially, was already imagining a massive repair bill! But thankfully, the vacuum switching valve was the culprit. Since you're at similar mileage to when I had the issue (mine was around 125000 KM), it makes sense it's wearing out now. Quick tip from my experience, while they're in there, have them check the vacuum lines too. My mechanic found a small crack in one of them and replaced it while doing the valve job. Only added about 20 Euro to the total bill but probably saved me from future headaches. Been about 8 months since my repair now, and everything's still running perfectly smooth. The fuel economy went back to normal within the first tank after the fix. Let me know how it goes with yours, curious if it's the same issue!

Thanks for such detailed feedback, everyone! Just got back from the workshop and wanted to update you all. You were absolutely right, it was indeed the vacuum switching valve! Had them check the vacuum lines too, following your advice, and they actually found a small crack in one of them. Really glad I mentioned that to them. The total repair took about 4 hours and cost 165 Euro including the new valve, line replacement, and labor. Been driving for a few days now and the difference is incredible, no more sluggish engine or jerky acceleration. Fuel consumption is already improving too. Really appreciate the help and advice, saved me a lot of worry about potential turbo issues. It's such a relief knowing it was a relatively simple fix. Car's running like new again, just as you said it would. Thanks again for pointing me in the right direction!