i have a 94 ranger with a 2.3L. I have installed an electric fan. What does the minimum temp need to be set at. As of now I have the cooling fan cycling on at 175 off at 160. Now it is getting cool outside and when I am running the heat in the truck it is overcooling and I think it is knocking the computer into "open-loop" or warm up mode b/c when the temps get down in the 145-155 range the truck burns very rich and the check engine light comes on most every time this happens. Or could this be another issue? Even with the stock fan the truck has always ran rather cool for a 4 banger. As far as I know the t-stat is stock. I might need to open it up to check and see if there is even a t-stat in it. Any help/suggestions greatly appreciated.