I have a 89 Firebird 2.8L and the fan will not go on with the car on. If I put a scan tool and the fan goes on. So it WORKS but my buddy says if you turn on the A/C the fan should go on. It doesn't. But I don't know if its because I can only do to the second power setting then it shuts off. But anyway, I replaced the relay, and the cooling fan sensor switch and still nothing. My firebird gets to 240 and stays put unless its city driving. City driving it slowly rises (I'm assuming because the fan doesn't work) water pump seems to work, with the radiator cap off when I rev the motor the coolant sinks and rises when I let off it. I also changed the radiator and I put the Air damn on.

What's next?!

 

fan switch, coolant temp sensor, test relay

 

Not good! If I were you I would ground the wire in the fan relay to keep the fan on constant until you at least find the culprit causing your fan issue, as the last thing you want to do is to have your engine averaging 240+ degrees on a regular basis, it is not good for the engine Nick...

 

No Air Dam under the car is the reason for high temps on highway. Cooling fans only work to about 40mph, so you are ok in stop and go city driving.