I have a 99 vw passat wagon 1.8 turbo. When it's cold out, the a/c is amazing. When it gets 90 or over, it works really cold when it idles at a stop light for a while, but it seems that when I'm driving normally, the air warms up a bit, then as soon as I'm at a stop light, it will cool it self down again. Can anyone please give me some insight as to why this is happening? In addition to that, it seems colder out of the passenger side than the driver's side.

Thank you