I am having an issue with my fan switch not turning on. A little back ground first: 1986 GT 3.4L. In the vegas heat, as long as I keep moving my car runs well below 200 (according to the gauge) . As soon as i encounter traffic slow down, it starts to heat up and moves right up the scale. I just had to replace the radiator due to a severe heat day and an accident on the freeway (POP). First thing I noticed is the fan was not on. I removed the connector on the fan switch and shorted the lead and the fan came on. I replaced the switch and the rad and it started to over heat the very next day; no fan. The only thing I can think of is either the new switch is also bad, or teflon tape is not allowing the switch to ground out. Any help is appreciated.