I had the same issue on my 2012 F30. It's the pneumatic wastegate flap in the exhaust. There's a dial you spin by hand to open or close. Since it's not electronic you can't just unplug a cable to solve the problem. What I did was a pain in the rear but it solved it... for now. I used a fishing hook that I shaved the points off of and used it to apply reverse pressure on the dial to keep the flap open. See pictures attached.
