AC not working and makes a hissing noise???

[Sarge]

Ok, so the ac used to makes a hissing noise through the vents for a few seconds when I first turned it on. As soon as the hissing stopped the air would blow nice and cold.
Now when I turn on the ac, the hissing is constant and won't go away...and the ac blows lukewarm. The compressor is kicking on, though. I also checked the low side pressure and it is good and full of refrigerant.

Does anybody know what this could be? I'm convinced that the hissing noise is the cause of, or linked to the ac not blowing cold.

Thanks for the help,
Hunter

 

[jwh]

Did you get this figured out yet? Mine is doing something similar. Was making a hissing noise. It doesn't seem to make the noise anymore and the AC is lukewarm. I just had the AC condenser and rad replaced due to a roadkill incident before this started happening, but I haven't had a chance to take it back to the shop yet to see what they have to say.