BMW 6 Power Loss & High Fuel Usage: VANOS Issues?

Hi there! I have some experience working on BMWs. I actually dealt with something very similar on my 2019 BMW 4 Series last year. The symptoms were almost identical to what you're describing. After taking it to my regular workshop, they diagnosed a faulty camshaft solenoid valve. The repair, including parts and labor, cost me around 250 Euro, but it completely resolved the issues, no more check engine light, fuel consumption went back to normal, and the rough idle disappeared. To help you better, could you share: Current mileage on your car? Any unusual sounds from the engine? Have you noticed oil consumption changes? BTW, if you're wondering about my background, I'd say I have moderate experience with BMWs, having owned both a 3 Series and my current 4 Series. Always happy to share what I've learned!

Hey, thanks for your detailed response! My mileage is currently at 91277 KM and had my last service about 4 months ago. No unusual sounds from the engine that I can hear, just the rough idle I mentioned. Haven't noticed any significant changes in oil consumption either. Just the power loss and increased fuel usage are really bothering me. Your experience with the camshaft solenoid valve repair sounds promising, it's good to know it could be fixed without breaking the bank. Really appreciate you sharing those details, might help me avoid unnecessary repairs. I'll probably get it checked at the workshop this week. Thanks for the help!

Hey again! Thanks for sharing those details about your BMW 6. The mileage and symptoms you described really confirm my initial thoughts about the camshaft solenoid valve being the culprit. Just wanted to add, after I got mine fixed, I learned it's actually a fairly common issue with our BMWs. The good news is that since you're catching it early (my mileage was higher when I had the problem), you're likely preventing any potential damage to other components. Quick tip from my experience, when you take it to the workshop, ask them to check the electrical connections to the solenoid as well. In my case, they found some minor corrosion on the connectors that they cleaned up during the repair. This extra step helped ensure everything worked perfectly afterward. Have you noticed if the symptoms get worse when the engine is cold? That was something I experienced with mine, and it might help the mechanics pinpoint the issue faster. Keep us posted on what the workshop finds, I'm really curious to know if it turns out to be the same problem I had!

Thanks for the extra insight! Yes, now that you mention it, the symptoms do seem worse when the engine is cold, especially the rough idle in the morning. That's really helpful to know about the electrical connections too, I'll definitely mention that to the mechanics when I take it in. I've actually just scheduled an appointment for tomorrow morning. Really hoping it turns out to be just the solenoid valve like in your case. The fact that it's a common issue and relatively straightforward to fix is quite reassuring. I'll update you once I get it checked out. Thanks again for all your help and sharing your experience, it's made me feel much more confident about getting this sorted out!