AC only cold at low speeds

[Nitronoise]

ok thoughts from the road out in the big rig ,,,,,,,, as my 2000 Buick Regal , is now only blowing cold air at low speeds on the road, in town , highway speeds cold air turns not hot but not cold

I stopped home and threw my gauges on it and it shows 50 psi low and i think 175 -200 high side ,, not positive but ambient was 90 degrees out last week end .
car historically uses /leaks about 8/10 oz of R134 every 2 years and it gets stored in the winter ,,, compressor was kinda noisy maybe oil is down???

its a garage queen and i want to take it to Indy for the drag races over labor day


thoughts and comments are appreciated

 

[clinebarger]

The pressure differential is on the low side which is usually caused by a worn compressor on a Orifice System.

As I'm sure you're aware....The Harrison H6 Compressor is notorious for leaking on these & leak quite a bit of oil with the refrigerant, Low oil is a death sentence for the compressor.