My 91 rs is running on the warm side.
I know the cooling fan was cycling properly a few days ago because it was idling at my buddy's shop and you could hear it going on and off.
2 days ago, I was stuck behind a backhoe on the highway for 5-6 miles at about 15-20 mph. Heat kept going up, cooling fan never came on, got to around 240 before I could get going and get some air through the radiator to cool it back down. Came home, parked it in the shop and let it idle, cooling fan never came on. It would come on with the a/c on, but not by itself.
Put it on ramps and pulled the coolant fan switch wire and grounded it, fan comes on fine that way. Plugged it back in- no go.
Replaced the switch today with the better 1 that napa sells, supposed to cycle in below 220, I think 208- can't remember.
Still have the same issue, no change.
I cannot reach ma voltmeter to the switch with it installed, but the switch body seems to be grounded.
Did I get a bad switch? That is the only thing I can figure.
How would I test these type switches, put it in an oven and check with voltmeter?
I don't want to go ghetto and make fan run when engine is running, but don't want blown heads either.
Any help is appreciated.

 

you can just go back to napa and switch the switch im a having the same problem sounds ghetto but you can pull the hvac/ fan fuse out and turn you a/c to the on position you radiator fan will turn on but not you a/c till you get it figured out and dont have to worry about blowin you heads

 

Ok, so my switch is not bad, new one is good, and so is the old one. I tested the old one last night. Did some temp testing today with an IR thermo and found my guage to be way off. It reads 25-30 degrees warmer than the actual temp, so I let car idle longer and sure enough, fan cycles on and off as it is supposed to. I am changing the cluster in the next week or so due to a failing spedo and failed odo, so I will get the guage reading correct then.

 

Buy a manual fan switch

 

Just my 2cents


Your fan motor might need replacing. It might not be making the proper revolutions...


Ususally motor replacement takes 10min and cost about $32......

 

Thanks for the ideas, but read my previous post, got it figured out already.

 

Oops i guess I didn't read that last post....lol