Hi there!!
What's the problem exactly?? Does the fan not work or does it only blow cold air out??
I had a problem with my Cavalier, the heaters blew out steam!!
It's because there was a hole in my Heater Matrix. (That's just like the main radiator in the car, but smaller. It's an air/heat exchanger which heats up the cold air with the hot coolant).
I added a bottle of Radweld to the coolant system, which I bought from my local car accessory shop for about 3 Pounds. Actually I used the Barrs brand cos it's better at sealing Heater Matrices.
If your problems the same as mine was, maybe you'll have a wet floor, probably in the passenger footwell. Although it depends on how big the hole is!!
Anyway good luck with it!!!
Glen, December 2005