Hi, I have a '92 535i 5spd, 167k miles, and have some a/c questions. When it is moderately hot out, say 70-80, the air works fine, nice and cold, cools car, settings 1 and 2 work well. Fan setting 3 and 4 though are noticeably warmer than 1 and 2. Also, my right side vents blow noticably warmer than my left side. I don't think my passenger side control works, possibly. My real complaint is when it is really hot out say high 80's to 90's and sunny, I have a black car, with black leather and am in the chicago area, it gets pretty hot here. Anyways, I can't adequatly cool the car, have to use fan on 2, which is the coolest air, because setting 3 and 4 aren't cold enough. I had my system completely charged last summer and a new dryer installed. this is how it worked back then as well. Will replacing my microfilter fix this problem?? Also, it sounds like a difficult job, what would this cost to have done? Thanks in advance for any answers.