[dwhisent]

OK, gave the diagnostics a shot. It gave a 166 at first, after resetting gave a 66, which from above indicates low freon. A bit tough to believe, since it began behaving like this immediately after the mechanic charged it and leak tested it, and after resetting (by disconnecting the battery) it cools great.

So maybe a bad pressure switch somewhere? Unfortuntely, I don't have a gauge set to test it with, but I might spring for one from harbor freight, only about $20.

Again, with winter approaching I have lots of time to figure this one out. I'll move on to questions about more critical issues using another post.

Thanks for the help!