BMW 7 Series Throttle Issues: Power Loss & High Idle

Hey there! I've got some experience working on BMWs (some experience with maintenance and repairs). Had a similar issue with my 2009 BMW 5 Series last year. The symptoms you're describing sound exactly like what I dealt with, especially that frustrating lack of throttle response! Initially thought it was the throttle body too, but it turned out to be a faulty accelerator pedal module. Took it to my trusted workshop, and they diagnosed it after running some tests. The repair cost me around 265 Euro, including parts and labor. They had to replace the entire pedal module because the electronics inside were shot. Quick question, have you had any other warning lights besides the check engine light? Also, does your car show any error codes? This would help narrow down if you're facing the same issue I had with my 5 series. For reference, I also used to own a 3 Series, and these electronics can be pretty finicky across the BMW lineup. Let me know the additional details, and I might be able to share more specific insights about your situation.

Thanks for the detailed response! My 7er has 146763 KM on the clock, and I'm actually dealing with these symptoms right after getting it serviced last week. I've got the OBD scanner at home and pulled codes P2015 and P0638. The throttle's definitely acting weird, sometimes it gets better after turning the car off and on, but then goes back to limp mode. Really appreciate the info about the accelerator pedal module, didn't even think about that being the culprit! Did you notice any intermittent behavior with your issue? This is driving me nuts since I need the car for work.

Hey again! Yeah, those codes actually ring a bell, had similar ones on my 5 series when I dealt with this. The intermittent behavior you're describing is super similar to what I experienced too. Mine would sometimes work fine after a restart, and I'd think "Great, it's fixed itself!" but nope, it would go right back into limp mode after a few minutes. When you mentioned it started after servicing, that caught my attention. In my case, it wasn't related to service, but these symptoms can definitely pop up when something's been disturbed. I remember sometimes my car would run fine for like 20-30 minutes before acting up again, which made diagnosing it really tricky. Since you've got the same codes I had, I'm even more convinced it might be the pedal module like in my case. The weird thing with these BMWs is that throttle-related issues can seem really similar whether it's the pedal module or the actual throttle body. My mechanic actually thought it was the throttle body at first too, but the diagnostic tests pointed to the pedal module. Quick question, when you're in limp mode, does your idle seem really uneven? That was another symptom I had that helped pinpoint the issue. Also, have you noticed any correlation between the weather and when it acts up? Mine seemed to get worse in damp conditions.

Thanks for all that info, you've helped me get a better handle on what I'm dealing with! After reading your experience, I'm pretty sure we're facing the same issue. My idle is super unsteady in limp mode, just like you mentioned. And now that you bring up the weather thing, I've noticed it does seem to act up more on damp mornings! I'm gonna get it checked out at the workshop tomorrow, and I'll definitely have them look at the pedal module first. Really hoping it's just that and not something more serious with the throttle body. Getting stranded because of this isn't fun! I'll probably update the thread once I get it sorted out, might help someone else dealing with the same problem down the line. Thanks again for taking the time to share your experience, it's given me a much clearer direction on what to look for!