the blower is inop when starting or at idle or low speeds, but when taken on the freeway it will suddenly come on, then when i slow down say under 40mph it will shut off please help. also when it does kick on the high fan works great but the medium and low dont work fully my email- r14tier@gmail.com

 

Fan works on high but not the other settings? You need a resistor or someones ford calls them fan speed control module. The blower motor resistor is what controls the speed of the fan, except in high speed, then it goes through a relay.