Hi there!
I'm kinda new to the whole bmw scene and I don't know where to start with this problem.
Recently my stock 2011 bmw 128i with 105k miles, the n52 engine, and a automatic transmission, started to stumble while idling at a light and will sometimes kinda jerk past 3k rpm. I only see about a 100 rpm drop when it does this, but it is enough to shake the car a bit. I don't have a check engine light on at all, which is making this a fair bit harder to figure out. I have had some small issues with injectors in the past that seemed to go away on its own with a bottle of injector cleaner and that has lasted me for 10k miles.
At this point the only things I can think of being the problem would be the vannos soleniods, spark plugs, or (hopefully not) something in the trans, but those options don't narrow it down much.
tweakbox appvalley https://vlc.onl/
Any help is appreciated. Thanks!