We just got a 2000 Grand Caravan about 2 months ago. It has about 94,000 mi in it now. All of a sudden, when you turn on the ac, it blows out hot air. It is almost 100 here, and this is not what I need now. What is the likelihood that it is just in need of freon and nothing more? I am bad with cars.

Let's say about 50/50. Open the hood, check along the thin pipeline running from the compressor (some call it the ac motor), through the condensor (the outside aircon radiator) to a little black tank that looks like a soda can. On top of this there should be a sightglass where you can see liquid flowing if the compressor is running and the freon is ok. If the engine is running and the ac is switched on, the ac compressor should be running - the inside part, the outside (pulleys) always run. If it is not running, first check the fuse for the ac, if the fuse is ok the ac might have a leak and then the pressure switch on the thick pipe side will prevent the compressor switch to engage - then the compressor won't run.

Check your ac piping, if it is oily, especially near flare nuts, it could indicate a freon leak. I'm talking about oiliness that doesn't come from the engine or tranny.

I hope this helps :)