BMW XM Boost Issues: Performance and MPG Troubles?

Hey there! I had very similar issues with my 2019 BMW X6 M last year. The symptoms you're describing match exactly what I experienced, poor acceleration, power loss, and increased fuel consumption. Turned out to be a faulty vacuum switching valve. These valves control the boost pressure actuator, and when they fail, you get exactly these symptoms. The garage diagnosed it pretty quickly with their diagnostic tool. The repair wasn't a major job, took about 2-3 hours total. It's not a serious issue if fixed promptly, but leaving it unfixed can potentially lead to bigger problems with the turbo system. The part itself is relatively small, but it's crucial for proper engine performance. In my case, they also did a full inspection of the turbo system while they were at it, which was reassuring. After the repair, the car ran like new again, all the power came back, and fuel consumption returned to normal. Just make sure you get it checked soon to avoid any potential complications with the turbo system.

Hey, thanks for sharing your experience with the X6 M! The vacuum switching valve issue you mentioned sounds exactly like what I'm dealing with. Would you mind sharing roughly how much you ended up paying for the repair? Also curious if you've had any related issues pop up since getting it fixed? It's encouraging to hear your car went back to running like new, that's exactly what I'm hoping for.

Hey again! Good to hear back from you. Yes, I can definitely share the costs, I paid 140 € for the repair, which included the new vacuum switching valve and labor. It was honestly worth every penny because the car has been running perfectly since then. I actually just had my regular service last week, and the mechanic confirmed that the boost pressure control is working flawlessly. Haven't had a single issue since the repair, the acceleration is crisp, power delivery is smooth, and fuel consumption is back to normal. It's such a relief when you get these things sorted properly! My advice would be to get it fixed sooner rather than later. The repair cost is reasonable compared to what you might end up paying if the turbo system gets damaged. Plus, you'll get back to enjoying the full performance of your XM, which is what these cars are all about!

Great news! Just wanted to update you all, I got the car checked out today and you were spot on! It was indeed the vacuum switching valve causing all the trouble. The mechanic I found was really professional and knew exactly what to look for after I mentioned our conversation. The repair cost me a bit more than yours, around 180 € total, but they also did a thorough check of the surrounding components. The whole thing took about 3 hours, but wow, what a difference! The car feels completely transformed, back to its powerful self with smooth acceleration and normal fuel consumption. The mechanic also showed me the old valve and explained how it failed. Pretty interesting stuff! Thanks again for sharing your experience, it really helped me make an informed decision and saved me from potentially bigger problems down the line. Time to enjoy my BMW properly again!