The switch would only work maybie 20% of the time, so last night I changed it. It still didn't work. I just went out there and grounded the wire, and it works fine. So the wireing is good, the switch is new so it should be good. But the fan won't come on by itself. Any ideas? Because i'm running out.

why don't you just run a manual switch... the universal kits... they're easy to wire and u can control it a lot easier settin it at 180 or 220 whatever you want... i installed about 6 months ago and haven't had a problem

I got a manual fan switch for about $3 at radio shack. It just gets annoying if I want to let the car warm up while i'm not in it or leave it idling, I have to remember to leave the fan on, or I get back and its overheated.

Well as mysteriously as it stopped working, it started again. It was probably me messing with the wires trying to find the problem problem which means my wireing or some connection is shot, so I guess I get to have some more fun with wireing. I'm going to keep the fan switch though, I can keep the temperature a little lower. Now I just need to put in a 160 degree t-stat to go along with it.

It's not just you - I'm crazy too!

I have a fan switch that works when i ground it, works when i torch it with the bic, NEVER works on it's own. Three new switches tried from 3 sources, no luck. Wires all test good. Switches all work under heat. Switches all work when grounded. Switches all work anytime they are NOT in car. Put 'em in car, no worky. Me gone crazy!

i'm not a big fan of 160 t-stat, thas just a little too cold for me, u might wanna just keep it at 180 there is nothing wrong wit that and u can still run hard wit it... just some personal experiences. About the fan switch tho... mine works fine and i've had it for a while never had to rewire anything and i suck at wiring...so make sure u are runnin the right wires to the right places... the switch will stop workin if its not amped right.