HI,I HAVE A STOCK 1989 FORMULA 350
It runs cool about 160 when driving,BUT when I come to a stop the temp rapidly climbs passing the mid way point and almost to 240.
I pulled over and lifted the hood and the electric fans were NOT running.however when I start the car the drivers side fan runs fine for about 10 seconds,then stops,and this is with the cars engine warm and temp gauge at the midway point.
If I turn the a/c on the right fan runs and cuts on and off and the left fan will run for a few seconds and start.I am baffled,can one of you thrid gen experts help?

 

I am having to same problem Im tearing in to it tonight so if I found someting Ill let you know

 

Thanks! hopefully you'll find the problem.
I havent ever had a thrid gen with electric fans before,so this problem is confusing.
What temp should these cars run at anyway? all my second gens run at 160-180.
Like I said when my 89 formula is moving the temp drops right away to about 150-180 and stays there until I reach a stop light (or rush hour traffic).
does it sound like the temp switch or relay?
Both fan motors ARE good.

 

Hi,I figured out what the problem was this morning.the wire going to the thermal fan switch on the passengers side head had become brittle from the heat of the exhaust manifold and broken off.
I fixed it and it runs fine now!