2006 PT Cruiser A/C issues

I have a 2006 PT Cruiser Limited Edition, 45K miles. The air conditioner is not working properly, as a matter of fact all it does now is blow hot air. It was acting up, intermittently blowing warm and cold air. When at a stop, you could hear the compressor cycle, and at the same time the car would jerk. Sometimes the a/c would blow warm air until I would make a turn or something and then it would 'catch' and just about freeze you out. A couple of times after I turned the a/c on, I heard a slamming sound like a vent was shutting. I also noticed a couple of times what appeared to be a vapor cloud come from under the left headlight area, and vapors coming in through the center vents. I took it to the Jiffy Lube to have the R134 checked. They told me that it was ok, but that the compressor did not cycle. So now, needless to say, I don't have cold a/c. I have verified that the fan kicks in, so that is working. It has never overheated, no check engine lights, no belt squealing. Is there any to bypass the relays or sensors to see if I can manually get the compressor to cycle, or am I just out of luck and have to take it to the dealer?
Thanks,
Jim Welsh
jimwelsh69@yahoo.com