Boy, this sounds like a similiar problem I've been having with my 91 300e with ASR.I' ve replaced the throttle pot and the throttle actuator to no avail.The output of the throttle gradually decreases until the car goes into limp mode . I've made numerous posts on this forum but have gotten few replies. These systems can be a real P.I.T.A. to diagnose. If I could find a true GURU on this system Id be happy to pay for his/her time.I too am ready to give up,but I will keep my car. I've figured out to hook up the throttle manually (deleting the e-gas system) only problem is I lose cruise control.....