This happens to me in mt 1989 300se, always at the same point every morning.
It is on a straight bit of road, where I put my foot down, but there is always traffic at the end, when I ease off the gas, the car seems to red-line and jerk a little bit before slowing.
What I can't work out is it is always at the same time, in the same place.

Weird!!!!

Oliver