Hi folks, Okay when I did the radiator flush the temp gauge would go to normal setting but when I turn the heater on full force the temp gauge would decrease and all I would get is cold air, turn it off the heater it goes back to normal. But when I detach the AC pump (electrically). I would get some warm air. (I think the heater control valve needs to be replaced as well.) And the temp gauge would stay normal but then slowly go down, till i turn off the heater, AC works good. 1997 Ford Ranger XLT supercab 2.3l engine. Standard 4sp w/od tranny.