"91 300CE - A/C problems - vent temp air then cold air??

[rgnprof]

OK, I bought this car today and driving it home the air didn't get cold until after 15 - 20 minutes or so. I drove it around quite a bit yesterday and I noticed it going to vent temps a couple of times, but for the most part the air was pretty cold. Today, it is blowing a kind of smelly vent temp air. Checked the pressures once I got home - High side 270, Low side about 40 - at 1500 rpm and about 90 Deg ambient temp. So, it's not a gas problem - anyone have any hints?

ryan