Well, I always seem to answer my own questions shortly after I ask them. He got started early today and looked at the AC and fairly quickly determined that the problem is a bad clutch in the compressor. It's heating up and then seizing. A good whack from a wrench makes it work for another minute or so. Rather than replace the whole compressor at $260, we're just going to try replacing the clutch (which should be a much easier job anyway), at which point I will hopefully be able to enjoy the car for the summer. -andrew #4115 Houston TX