BMW X4 Rough Idle and Stalling, IAC Valve Issues?

Hey there! I've got some experience working on BMWs. Had a similar issue with my 2017 X3 last year. Like you, I was getting rough idling and stalling. The symptoms you're describing sound really familiar, my car was doing the exact same dance. Took it to my regular workshop, and after diagnostics, they found heavy contamination in the intake system. Turns out it needed a thorough cleaning and some parts replacement. The whole thing set me back about 425 Euro, but it's been running smooth as silk since then. Before I share more specifics about the repair process, could you share: How many miles/kilometers are on your X4? Have you noticed any loss in power while driving? Any unusual sounds when accelerating? These details would help me give you more relevant advice based on my experience. Let me know, and I'll help you figure this out!

Thanks for the reply! My X4 has 79190 KM on the clock and just had its service last month. Actually, I have noticed some power loss, especially when accelerating from a stop. There's also this subtle rattling noise that seems to get louder with acceleration. Your experience sounds pretty similar to what I'm dealing with. I've been hesitant to take it to the dealership because of the costs, but if cleaning and parts replacement fixed your issue, maybe I should just bite the bullet and get it checked out properly. Did your mechanic mention how long the entire repair process took?

Hey again! Yeah, those symptoms you're describing are exactly what I experienced with my X3! The rattling noise and power loss, it's like déjà vu. My repair took about 4-5 hours total. The mechanic had to remove several components to access the intake manifold for proper cleaning. Actually, based on your mileage and those additional symptoms you mentioned, I'm even more convinced it's the same issue I had. The rattling noise is a dead giveaway, that's what really rang the alarm bells for me too. My mechanic explained that carbon deposits can build up over time, even with regular service. Quick tip from my experience, make sure they check the throttle body while they're at it. When they fixed mine, they found it needed cleaning too. That was actually causing some of the power loss issues. I know the dealer costs can be scary, but honestly, putting it off might lead to bigger problems. Mine was running terribly before the fix, but it's been perfect for over a year now. Totally worth the investment in hindsight. Let me know what you decide to do. I'm curious to hear if it turns out to be the same problem!

Thanks so much for all the detailed info! Your experience has definitely helped me make up my mind. I'm going to schedule an appointment for next week to get it properly checked out. The fact that your car has been running perfectly for over a year after the fix is really reassuring. You're right about not putting it off, I'd rather deal with it now than risk bigger issues down the line. The similarities between our situations are too close to ignore, especially that rattling noise and power loss. I'll make sure to ask them to check the throttle body too, as you suggested. Really appreciate you taking the time to share your experience. I'll update you once I get it sorted out and let you know if it turns out to be the same issue. Thanks again for all your help!