About a 3 weeks ago I noticed a weird thing with my a/c a couple of times where it was blowing cooler on the passenger side then the drivers side, and no I don't have dual controls. Last week I was 2 hours into an 8 hour trip and my usually awesome running 99 Grand prix started hesitating on acceleration. A little while later I pulled into a rest stop. All the while my a/c seemed to be running fine or maybe just slightly warmer than normal. I shut the car off for 10 minutes. Got back in and headed down the road, the hesitation was worse. Then all of the sudden my a/c starts blowing warm air and the hesitation immediately goes away. Car ran great the rest of the trip but no a/c. When I got home I tried to add Freon but it was full according to the psi. I am a female and don't have a lot of brut strength but when I look I can see that the compressor and the clutch are running when I turn the air on. The indicator light on the interior heat and a/c unit illuminates when I press the a/c button. There was a relay fuse under the hood for a/c which I swapped out with the one labeled horn ( which I know works) and it made no difference in the a/c. I took the one out that is labeled a/c diode out and since I didn't know what I was looking for it looked normal to me. I then checked all the fuses in the glove box labeled hvac and all were good. Any pointers on anything else I could check out for a possible easy solution? Thx