09-29-2021, 03:02 PM
Have you checked the belt tightness to the water pump, as well as the one to the alternator? I had one overheat a while back when the when the alternator belt became worn and loose. Might seem weird, but the belts balance out tension in some manner around the central pully. Higher RPM would overcome some of that so idle would be hot and some cooling with higher pull at higher RMP.
