AC Wont Blow Cold

I have a 93 toyota celica gt 2.2l when I first bought the car it needed to be recharged because it was low. It first had r-12 but I let all that out and I put in r-134a with a interchange kit well it still wont blow cold air but the compressor is now kicking on. I put as much coolant as it will take but nothing. So I let all that out and disconnected the lines to the accumulator/drier or whatever it is and thick chalky black milkshake stuff came out. Is that normal or no? Looked like chocolate milk except it stunk really really really bad. Is that most likely the problem or does that not matter?