Mechanical Problems & Technical Chat - QUestion about Ac problem with Honda civic?

I have a 91 civic SI, i have added the R-134A freon it blows cold for like a couple of hours. What could it be? I have replace the reservoir cause it was damaged. I also read that it may be the A/C expansion valve?? Please advise
[/align]

Works for a couple of hours, then what? Can you park the car for a while and turn it back on and it's cold again?

no once it goes back to blowin hot air it never goes back to blow cold air

Sounds like you have a leak in your system, unless you repair that leak it will just keep doing the same thing.