So, it has been almost 90 degrees here in the Pacific NW. Unheard of for this time of year. Anyway, this is the first hot spell since I have owned this car. The A/C gets cold for a bit, then warms up, and repeats the cycle but without any rhyme or reason. I assume the R-134a needs a boost, but have no codes or low refrigerant message. Is it possible to need refrigerant in a Cadillac and not have the message or code displayed yet? Assuming it needs a boost, is the stuff from the auto parts store good enough? And assuming it needs a boost, it must have a leak, correct? So, I was considering the R-134a with stop leak from the parts store. Opinions? I have some gauges somewhere in the garage, unless they got thrown out in our recent move...haven't been able to find them, yet.