SSort

I have a 77 450sl with 115k. It runs fine except on very hot days. It seems to happen when the engine temperature is around 200 degrees. It will not idle with out my foot on the gas pedal. Also I have not seen my aux fan kick on yet. I have replaced relay,& temp.sensor & both seem to work properly. I also powered the fan direct and it works fine. Is there any connection between the temperature running hot & the engine not idling properly. Any suggestions would be appreciated.