I believe the solution is a replacement of the rubber bushing around the frame portion of the linkage on top of the valve cover. I have that same friction point about halfway down the throttle and it makes my cruise very unhappy.

PM sent MBZ

http://catalog.peachparts.com/ShopByVehicle.epc?q=&yearid=1983@@1983&makeid=63@@MERCEDES+BENZ@@X&modelid=6207%3AED%7C10000134%3AMBC%7C1510@@300SD&keyword=throttle@@throttle&catid=All@@All&subcatid=P%3A240696@@Throttle+Bushing&applicationid=W0133-1629530@@Throttle%20Bushing&mode=PA

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