Allan-
Unfortunately I have much experience with this issue. There are typically two culprits--the throttle actuator or the ASR switch. The actuator is very expensive, and you might be able to find a disable switch for the ASR unit. Beckman Technologies rebuilds the actuators with a one year warranty (same as MB). As for your dealer telling you they haven't seen the problem--right!!! I have contacted 3 dealerships in South Florida and they average 5 a week.