going from a 62mm to a 70mm shouldnt have any effect at idle, the throttle plate is closed. the fitv makes sense, but the bigger tb opening doesnt have anything to do with it.
I guess I should have clarified it. When the car is in park, the car idles fine, maybe a little low. When I put it in drive or reverse and press on the throttle, thats when it starts sputtering and almost dies.
