Thanks for your reply, This is a 1995 E300 (diesel).
While in Drive, but stopped at a redlight it idles okay at 550 RPM, but if I put it in park for a minute it used to idle at 950 RPM. The dealer adjusted the linkage and it does 750 RPM instead of 950 PRM.
My 1987 300D idles at 550 and doesn't seem to have a "fast" idle.
Is 750 RPM normal?
They have replaced the steering linkage and there is still a shimmy, so the car is already going back. Should I ask for further adjustment on the idle?