Have an 02 S4 B5; when I put the AC on, it comes out cold, then I hear it click off in about two minutes, and it starts blowing in warm air, then it clicks on again, and starts blowing out cold air... WTF? I put it on auto and put the temp on low, so it's not like it's meeting the temp it's set to and turns off... It's really strange. Has this happened to anyone?

 

Yup! You need a re-charge...eh, simply goto you local auto parts store and get a R134a regharge kit.(about 15$) Then open the hood and remove the panel that goes across the wipers and battery.(not just the battery) Facing the car on the left under the panel are 2 black caps. Unscrew them to find what look like tire pressure valves. The kit will only fit on one.(called the low pressure) Follow the instructions on the kit and you'll be fine.

 

Cool, Thank You!!