Originally Posted by TieRod

I've heard of this problem in the past. But it was on cable operated TB. They would add a bigger spring. Not sure what to do on a DBW. Thats alot of air goin through a 75mm TB. Maybe a 90mm would help slow down the velocity where it could shut.

Originally Posted by 4.8T

i meant is there another tb you could try. i understand that its new but i've never really heard of anybody having them stick open during boost.

how long does it stay open? have you data logged etc desired position to see if the thing is being told to stay open. is the fueling there for the position of the throttle? does it go lean when it stays open?