So i took my car out drifting today and realized i have a problem with my throttle. at the end of my drift with the pedal still pinned the throttle will cut out pretty much completely and the rpms drop to about idle or below. with the pedal still pinned while the throttle cuts out, it will eventually come back in when i get down to about 10mph or so. also while doing doughnuts it does the same thing. just in case it matters my z is a n/a and i swapped it from an automatic to manual. i am still running the factory auto ecu. i have an intake, test pipes, catback, and an adjustable fuel pressure regulator. thats about it for engine mods. any insite would be much appreciated.