Hello all, first post here...hate to come in with a problem as my first post, but have a major, possibly high dollar problem.

My A/C unit blows cold only for a few minutes, then goes warm. Turn it off for a little while, like 10 minutes, and it goes cold again, but only for a few more minutes.

The weird part is that if you crank the truck, let it idle, turn on the A/C, the AC will freeze you, and I'm talking here in the deep South in July & August! I left it ideling like that for 45 minutes, and almost froze when I got in the truck to check on it.

Freon level is good. One mechanic thinks the compressorclutch is weak...I dont know. One suggested the high pressure switch is going bad, or bad already.

This is a 1999 Sierra Z71, 5.3 L gas burner, with about 175K miles. I've had it about a month now.
Help!!

 

a DCECENT tech should be able to find that....Most LIKELY cause is the cycling switch...or the clutch