Hi All,
I have a 2013 Av, 5.3L. Today the AC started blowing hot/cold cyclically while driving around town. I threw the gauges on when I got home, and found Low ~25, High ~ 170 @~80*F. I added about a can and a half of R134a which brought the pressures up to around Low ~48, and High ~215 @ 83*F. The problem is the compressor still cycles continuously. It will reach the said pressures above, and the compressor immediately kicks off for about 10 or so sec, and back on again. The cabin vent air, of course is ranging from 68-80 degrees. I was originally thinking (before I saw it was low) a bad/clogged orifice tube, but now I am thinking the compressor is on its way out. Thoughts?

 

You can put a voltmeter in the compressor plug to see if the voltage changes, that would tell if the compressor is at fault if the voltage stays the same.

 

Thanks for your help. It led me to a faulty pressure switch. Seems to be doing ok now.