a/c pissing me off

[chronoti]

so i'm at my whits end with this bloody a/c.

so far

7am-3pm works fine

4pm - ??am doesnt


known:

fans work!
compressor clutch engages!
no bubbles in the sight glass!

unknown:

pressure when not working.

so i elimated any underhood issues as that they would be apparent after the engine heats up and heat soaks everything.

so it has to be something incab. i wount be able to get my gauges till Tuesday. could it be for some reason the thermostat on the evap, a/c amp system (no idea on what this thing does), or the expansion valve.

for the expansion valve i read something about heat tube thing that opens it up, what the hell is this, i'm new the this fancy samcy r134a. help?

also a/c light doesn't blink ...... the fricking hell