My A/C starts ok, then after driving for some minutes, as it is irregular, it goes off and just blows warm air..and then sometimes comes back on if I turn the engine off, or might just come back on on its own...and if its raining, when it goes off the defroster doesn't work. My mechanic has replaced the control box in the dash a couple of times, and says it sounds like its the compressor, that the bearings are bad and just keep heating up and stop....though after reading some of the threads here I am not so sure. I have found compressors on Ebay for cheap, but my mechanic claims that the Turbo engine requires a different compressor than the non-turbo engine..any thoughts?