Hey guys. Had to ask this after today. I can't take it anymore.

When I downshift and punch it to pass someone or merge on a highway, the car pulls great until exactly 4000 rpm, where it literally feels like the car falls flat and someone is pulling against it from behind. It maybe gets mildly better higher in rpms, but the car just has nothing after 4000 rpm, that I actually shift earlier to drive it below that. The pull down below is much better.

This flat spot is way worse than the 2800-3000 rpm sputtering that I also have, and improved greatly since getting the car.

So I've read about the DISA causing this and various other things. I've seen BMW service bulletins to address this that says to replace the DISA and reflash the DME to reset the knock adaptations.

Link 1: https://forum.e46fanatics.com/showth.../285819?page=2

Link 2: http://www.zhpmafia.com/forums/showt...highlight=4000

Link 3 (fixed with new DISA only): http://www.zhpmafia.com/forums/showt...highlight=4000

My question is what should I do? Replace DISA and flash DME? Can that be done not at a dealer? It sounds like if the full flash doesn't happen, then the knock adaptations don't get reset.