Ive got the factory guages in the truck, and in summer months the guage will read just a little to the right of center or 90 degrees, in the winter it stays a little to left. After it warms up and the thermostat opens, my heater runs cool air. Runs good and hot prior to thermostat opening. Blower motor, heater resistor, and fan/heater switch work fine. So I guess that I should try and shunt the air flow into the radiator then? I will also check the antifreeze/water mix. If not enough water in the system that would cause it to run cool also...right?
