BMW 4 Series Stuck in Limp Mode, No Power Response

I had a similar issue with my 2013 BMW 3 Series last winter. The symptoms were exactly what you're describing, sluggish response, high idle, and that annoying limp mode. Turned out my accelerator pedal module was failing, causing communication issues with the throttle control unit. Got it diagnosed at a garage and they found corrupted signals from the pedal sensor. It wasn't just a simple fix, they had to replace the entire pedal module assembly. The electronic components inside the pedal were toast, which is apparently not that uncommon in these models. It was definitely a serious issue that needed immediate attention since it affects basic drivability and safety. In my case, the car became barely drivable within a few days of the first symptoms. Based on your description, I'm pretty confident you're facing the same problem. My advice? Don't drive it more than necessary and get it checked soon. The throttle valve could be the culprit, but have them check the pedal module too. These symptoms are too similar to ignore.

Thanks for sharing your experience with the pedal module issue! That's actually super helpful information since I had no idea the pedal sensor could cause these problems. Quick question, do you remember roughly how much you ended up paying for the repair? Also, has everything been working smoothly since they fixed it, or have you noticed any other quirks?

Hey there! Glad to help update you on what happened after my first reply. So yeah, it ended up being spot on, I took it to the mechanic and they found that pesky throttle valve was definitely causing the trouble. Got that sorted out and also had to deal with the accelerator pedal module which was acting up. The bill came to 265€ for fixing the electronics in the pedal module. I've gotta say, since getting it fixed, my BMW's been running like a dream! No more of that annoying limp mode or sluggish response, it's back to being the smooth ride it should be. It's been several months now, and I haven't had a single issue pop up. The pedal response is perfect, idle speed's normal, and that worrying check engine light hasn't made another appearance. Honestly, it was worth every penny to get it properly diagnosed and fixed. Sometimes these electronic gremlins can be tricky to pin down, but once you get them sorted, you're good to go. If you're still having issues with yours, I'd definitely recommend getting it checked out, sounds exactly like what I went through, and the fix isn't as scary as it might seem!

Thanks everyone for the helpful feedback! I wanted to update you on what happened. I took the car to the mechanic yesterday, and wow, you were right about checking both the throttle valve and pedal module. Turns out my throttle valve was acting up, just as I suspected, but they also found some issues with the wiring connected to it. The mechanic was actually pretty straightforward this time. They showed me the faulty parts and explained everything clearly. Got it all fixed up for about €350, which wasn't as bad as I feared. The best part? My car's running perfectly now, no more sluggish response, no more check engine light, and the idle speed is back to normal. I'm really glad I asked here before going in. Having some idea about what to expect made the whole experience less stressful. It's such a relief to have my car back to its normal self. Thanks again for pointing me in the right direction with this!