Have you checked the PTU? I took my radiator out one day and it rattled the PTU, so when I started the car it was only running on 3 cylinders. Just unplug it clean the corrosion from the connectors, and maybe apply some of that electric grease. That fixed my problem, and cost like 2 bucks lol. Really amazing the difference it makes.
I need to replace and rewire mine because it still loses power when I move the PTU.
Hopefully yours is an easy fix too!
If I would have known addiction was this expensive I would have seen a shrink a long time ago. --BadZCar (FL)