More A/C Woes

[jpinvictus]

I could use some ideas.

I recently fixed an A/C leak in my 97 vr4 with ACC, replaced the evaporator, drier, and expansion valve, new o-rings, etc. Had it professionally leak tested and it cleared. Ice cold air. Woohoo!

2 weeks later, the temperature in Louisiana is at 95 degrees and sunny as hell, and my A/C is blowing somewhat cool while in motion, and barely cool at all while idling. I thought maybe I didn't get the leak, and it was just super slow, which is why it passed the leak test. I decided to pay a shop $20 to hook the gauges up in hopes that maybe they'd see something I missed.
Gauges said my pressure is still perfect! Unfortunately it was only 70 degrees outside and rainy, so I couldn't replicate my issue while there, which brings me to the next part:

I've noticed if the temperature outside is below 80, my whole car is ice cold. The a/c works amazing, I have to turn it off or I freeze. But when its 90 degrees out, it's shit. I get out and I'm drenched in sweat. Oddly enough, the heat from the sun seems to affect it in a noticeable way. If it's 85 and overcast, my air blows significantly cooler than 85 and sunny, it is so noticeable that if I ride down a shady road for 5 minutes the air is noticeably cooler.


It's much worse at idle/low rpm ranges.
The condenser fan is working, and by that I mean when I turn the ac on, both fans kick on and blow fast enough that it'd hurt my fingers to try and grab them.

My biggest suspicion right now is the belt. I just recently started getting some belt squeel when I turn my a/c on in 1st and 2nd gear, would that produce these kind of symptoms? Should I be looking somewhere else first?

I don't know what to do next to diagnose it. Where do I go from here? The a/c shops around here are not too great, I don't really trust them, so I'd like to figure this out for myself.