Why my 1996 buick century car air conditioner blows vent air only?

it's a buick 1996 Century with a 3.1 engine. I've checked the freon and it's find and I've ckecked the switch and it's find also.Why my 1996 buick century car air conditioner blows vent air only?First of all, I'd like to point out that to check your freon, you need to have a set of manifold gauges hooked up to the system with the system working to read the pressures. So there is no way you can say that your freon is fine if the AC isn't working. There may be freon in the system, but its probably not enough to engauge the low-pressure switch.



If your freon is indeed ok, then look at the compressor. You will notice that the outside is spinning with the engine, but the center of the pully stays stationary. If you measure the voltage coming to the compressor (there should be a plug with 2 wires, a switchced power and a ground) you will find it to be 0-volts. Follow that wire back and see where you lose your voltage. I'll mention again, that the wire which activates the compressor traces to the pressure switch, so low freon would cause voltage to be lost there. Then it goes to a relay which is activated by the switch in the dash, and ultimately to a fuse which is either under the hood or under the dash.



Hope this helps.