[TeflonJack]

I own a 93 Taurus SHO. Last year I replaced the A/C compressor (with new clutch), orifice tubes and even the accumulator. This was a rather expensive job. However, afterwards the A/C worked like a dream, the car got cold very quickly with MAX A/C. However, this year I noticed that even though cold air is blowing out, it seems like it isn't coming out of the vents at full force. The vents air speed does decrease when the fan selector knob is increased and decreased, but at like 1/4 output of what it used to be.

I brought the car in to get checked for a leak and they found no leaks or anything wrong with the A/C system (the AC Compressor was turning on and the clutch was working properly). They placed more R134A refrigerant in and it was nice and cold for about two weeks, and now I am back at the same problem. I heard that I may have a vacuum line problem. Is there anything else I should be on the lookout for or a way I can diagnose this problem myself. Could this be a relay or a switch, since from experience SHO are known for electrical problems?

Thanks.