88 260e throttle goes wide open on start up
 

I have an '88 260e which runs rather well with the exception of right after starting the throttle goes wide open.
More so when it is cold and damp. If I put it in neutral it will not happen.
The gas pedal and throttle cable and linkages are not binding or hanging up.
Other then this it starts, runs, and idles perfectly.

I was suspecting the decel microswitch but I do not know how to test it and don not want to jsut start throwing parts at the issue.

Any suggestions from anyone out there?