Got my 2188 out of my friends shop today. As a last minute request, I asked them to check the A/C pressure and see if I was low on freon. They said the freon level checked ok. I needed to leave with it and on the way home, I'm still not getting a "sharp" cold temp of air out of the vents. just cool air. I know the evaporator is clean, the condensor is clean and the air return behind the seat is not restricted. Any ideas what could be wrong. A guy I was talking to said it might be the expansion valve has failed. What do you guys think?