not basing this on any kind of actual experience or what not....
but i would check your engine cooling system - fans (both clutched and electric) and coolant.
i imagine that with todays ecu's, it would cut the ac compressor out if your engine was running hot. kind of like how if you go wide open throttle (wot) while the ac is on, the ecu will cut the compressor.
so, check to make sure you have plenty of coolant, and check to make sure your clutched/big/main fan seems to blow harder (can always tell by reving slightly and you'll sound like a mack truck), and check that the electric fan in front of the radiator is also kicking on.
but that's just my theory, or the hurricane did it
