Today while pulling into traffic my A/C stopped blowing cold. I wasn't at WOT but I was giving it a good bit of gas. After about 2-3 minutes I smelled something burning. I pulled over, lifted the hood, and there was smoke coming from my compressor. After about 5 more minutes it stopped smoking and the A/C began to blow cold again. It blows really cold air just like before but now it whines and knocks really loud. WTF happened??

 

The smoke was most likely your serp belt melting, meaning something is binding in the compressor.

Clutch/Pulley is binding.
Iced up compressor. (was it or any of the hoses covered in ice?)
Low on freon (the low pressure switch should have turned if off though)
High on freon (overcharged).
Blocked system.
Low on oil.
...and about 25 other things.

Pull the serp belt off and check for binds in the pulley.
Other than that, you will have to get a set of gauges on it and see what's going on.

 

Just went thru the exact same thing.The bearings for My A/C clutch had burned up and froze. With the car off you can loosen up/take off the serpentine belt and jiggle the AC pully. It should not have any kind of play in the pully. Also it should be able to spin freely with the belt off. Mine was really rough spinning and made all kinds of noise. If thats the case, you need to change the AC Clutch.

 

I can actually move it with the belt on.[:'(]I was thinking it might be the clutch...or hoping that's all it was. How hard was that thing to replace? Thanks for the help guys.

 

Not too hard to replace at all. Here is a guide I used (http://autorepair.about.com/library/faqs/bl168i.htm) The hardest part I had wasputting on the new field coil and getting it to sit flush on the compressor (it took some hamering). The AC clutch cost $137 andthe snap ring pliers were $17 at autozone (you can get them for $5 at harbor freight if you have one around). Also you can rent the AC pully remover from Autozone.

 

Cool. Thanks again for the help. Well, I guess the rest of my day is accounted for.[8D]

 

Yeah, shouldnt be too bad. Hopefully you have better luck than I did. After installing mine, My AC still wont kick on. I seem to have a switch or fuse that went out as well.