BMW X4 VANOS Problems: Multiple Issues Plague Owner

Hi there! I've got some experience working on BMWs, not an expert but I know my way around them. I had very similar issues with my 2013 BMW X3 last year. Same symptoms, check engine light, worse fuel economy, power issues, and rough running. Initially thought it was the VANOS too, but my mechanic diagnosed a faulty camshaft solenoid valve. Had it replaced along with some wiring repairs in the power supply for about 250 Euro and it fixed everything. Could definitely be related to what you're experiencing on your X4, but would need to know: What engine variant do you have? Any specific error codes from the CEL? When did these symptoms first appear? Have you had any recent work done on the engine? Let me know these details and I might be able to share more specific insights from my experience.

Thanks for your detailed response! I have the 2.0L gasoline engine variant. Last serviced about 5000 KM ago, and symptoms started appearing gradually over the past month. Haven't done any recent engine work. Really appreciate sharing your X3 experience, I'll definitely have my mechanic check the camshaft solenoid valve. My mileage is at 145257 KM, so these kinds of issues are starting to pop up. Haven't pulled the error codes yet, but planning to get that done tomorrow. Did your X3 also have a slight vibration at idle when the issues were happening?

Yeah, I can totally relate to what you're going through! My X3 absolutely had that vibration at idle, it was actually one of the most noticeable symptoms. It would get particularly bad when the engine was warm and sitting at traffic lights. Really annoying stuff. The mileage on your X4 is pretty similar to what mine was when I had these issues (mine was around 150000 KM). Since you've got the 2.0L engine like I did, it's sounding even more similar to my situation. The gradual onset of symptoms matches my experience too, started with just slightly rough idle, then progressively got worse over about 3-4 weeks until I couldn't ignore it anymore. Quick tip from my experience, when you get the error codes checked, make sure they do a complete scan. My first scan only showed one generic code, but when my mechanic did a more thorough BMW-specific scan, it revealed the actual camshaft solenoid issue. Also, while they're checking it out, might be worth having them look at the electrical connections around the solenoid. In my case, there was some wear on the wiring that was contributing to the problem. Better to catch all issues in one go rather than having to go back again. Let me know what the error codes show up, really curious to see if it's the same issue I had!

Thanks so much for all this information, it's super helpful to hear from someone who's been through almost the exact same thing! The vibration you described at traffic lights is exactly what I'm experiencing. Really good to know about getting that BMW-specific scan too, I'll definitely request that when I go in tomorrow. You've actually made me feel a lot better about this whole situation. I was worried it might be something major (and super expensive), but a camshaft solenoid valve sounds much more manageable. I'll keep an eye out for those wiring issues you mentioned too, great tip about checking all that in one go. Will definitely update you once I get those error codes tomorrow. Can't believe how similar our situations are, same engine size, similar mileage, and identical symptoms. Fingers crossed it's as straightforward a fix as yours was. Thanks again for taking the time to share your experience in such detail!