I just dropped an 85 190e 2.3 motor into my 1986 190. The problem I am having now is the engine turns off when under heavy throttle. If I mash the throttle to the floor and the rpms rev, the engines starts to turn off. While driving, if I pop it in neutral, it will keep running. However, if i stay in gear with a little throttle, the car will backfire and shut off. Any ideas of what may be my problem. thanks