Dove into checking the AC system out today. I first bought a can of of this Avalanche Refrigerant. When I hooked up to the port the system was showing low at 15-20 PSI. Which was good news that it wasn't totally evacuated or contaminated. Here is a pic of the can and the gauge that domes with it. it's 18 0z.
Once about half that can was in and it hit about 35-40 PSI the compressor started to cycle on and off. I put the full can in and ran it for a bit and it continued to cycle, air out of the vents got semi cold.
I noticed the high line was a bit dirty and oily covered. There may be a seep from the high pressure port/valve or o-ring at that orofice connection. I got some wrenches and snugged up that connection.