I have a 2000 626 with 131,000 mi.I just bought. The AC has never been cool enough, especially while idling(might as well have none!).I can hear the compressor kicking on/off constantly.The RPMs jump up and down and when idling the car will shut off. It will also start to overheat at idle, I can see the temp gauge start creeping up almost as soon as I stop at a stop light. If I turn off the AC the car has a lot less problems.At 130,000mi the AC compressor,oriface tube,spark plugs, air filter, fuel filter, and oil was changed(other than that I have no clue).The thermostat and belt have just been changed. Can anyone help me out, what could be wrong?