fan problems on 1994 pontiac sunbird?

The first thing to do is make sure the fuse you are using is the correct Amperage for that circuit. If it's too low, it will blow even if everything else is fine. Don't use higher than recommended either though. That defeats it's purpose. Check your Owners Manual for the right size, or for a diagram on a cover maybe.

A short-circuit would make it blow right away. A disconnected ground wire would make it not run at all. A ground wire touching somewhere it shouldn't would have no effect. So we can rule all those out as the problem.

The problem is most likely too much resistance. Either physical, like bad bearings, which you might be able to tell from turning the fan by hand. Wait until the engine is nice and cool, like in the morning say, and try to turn the fan by hand. If it's hard to turn, that could cause it to take too much juice to turn it. This would also show up as a high Amperage draw.

The other type of resistance is electrical. This is more difficult to check with out the proper tools, but if your wiring connections are good, it is most likely in the fan. A good mechanic with the proper test equipment could do a voltage drop test of the control circuits, and/or an Amperage draw test of the fan motor to make sure where the problem is.

But if you want to gamble, I'd bet on the fan.

Could be an electrical problem. A ground could be loose or touching somewhere. You should have it checked out by a mechanic.