i have a 91 rs tbi, the other day the cooling fan wont stop running , it also comes on immediatleywhen i start the car. could this be an ecm problem besides the fan switch. i looked at the diagram, but i cant figure out if the ecm can also power the fan too??

 

On the single fan cars only the switch controls the fan, the ecm has nothing to do with it, i have a similar problem with an aftermarket fan switch. The problem is most likely the switch or the fan relay. Hope this helps