well if your gain setting is up to high your car will over boost, its a 1-100 setting, mine is set at 12-15 im not sure if aftermarket turbos can be set higher but have a play try setting at 15 and see if it still does it, not sure if you also know that when changing the setting the controller will take 3 or 4 learning runs before it sets itself so you will need to do 3 runs up to high revs see if it makes a difference anyway. do you have a manual for it because i can post one up for you. is it the id3 that you have?