Ok I have a 1987 Trans Am 305 5.0 v8 4bl carb. My fan has stopped working. If I run car long the temp will quickly rise and the car will get extrtemely hot. Probally overheat and destroy the block or radiator if I dont turn it off. Fan doesnt kick in at or before 250, infact it never kicks in. I've bought two different brand new relay switches and that hasnt helped. I flushed radiator and checked water pump, all that is fine. Now I dont think the fan itself is messed up because my pops made some invention that runs a wire from the fan to the positive battery cable and the fun will run constantly and fine keeping the car very very cool. Now you can imagine its very annoying. Turning car on, opening hood, connecting the wiring then going back into car to drive. I have to do this constantly if I go a considerable distance. Im also sure this isnt good for the fan or the cars battery, nevermind the annoyance. I need help here. What could the problem be?

 

Change the coolant temp sensor.

 

Now I dont want to sound dumb, but I really suck with names. Thats not the same as the thermostat is it, because I did that twice as well. If not can you be more clear as to what that is, what that does, and where it goes. Like I said I suck with names. I just know **** by looking at it. Thanks.

 

The sensor/switch is on the side of the head, under the exhaust manifold, also check to make shure the wires are ok.




http://www.hawksthirdgenparts.com/in...ROD&ProdID=915


That's the one I have along with a 160 thermostat, even if that's not your problem, once the problem is fixed it helps your motor stay cooler.

Or you can wire it like this.........
https://www.thirdgen.org/forums/atta...an-fandiag.jpg

 

its the fan switch, not the coolant temp sensor, different sides fo the engine, different jobs.

before you start changing parts, though it is probably the fan switch, check it first. Usually the fan switch is located in the head, on the passenger side between the rear two cylinders, it a oval shaped plug with one wire going to it picturd above. turn the key to the run position, Pull the plug off, get a little piece of wire, stick one end into the cap, and ground the other end to the engine block. If the rest of the wiring/controls are working, the fan will turn on, if then fan does not turn on, the fan switch is bad. If it is bad, get an aftermarket fanswitch that turns the fans on at a lower temp. the stock switch turns on at 238 degrees, look for something around 200, it will help the cooling process a bit.

 

I'm having the same problem. Grounded the wire for the fan switch it came on. I replaced the fan switch with a 180 switch and the fan still will not come on. The temp gauge will go up to 230 and still wont come on.

 

If you are grounding that wire and it comes on, then I would say that maybe the new switch you put in is possibly bad.

 

I took the switch back out and returned it, and installed another one. And the still fan still dosen't come on.

 

Are you getting coolant to the switch?

 

I think so, when I took the switch out to replace it I burned the H out of my hand with coolant

 

If you ground the wire going to the switch and the fan kicks on, I would think the everything is working like it's supposed to except the switch.