This one is driving me crazy cuz im a complete noob when it comes to a/c system. I hope you guys can help!. My problem is that when i go to turn on my A/C it doesnt work. i hear the hiss of the vaccum, and then nothing, but if i drive it around town and hit a good size pothole boom! it comes on and then will stay on until i turn the car off. also my max fan speed doesnt feel as strong as it used to be. Also if the system is off you can feel hot air or cool air still creeping thru the vents depending on what temp setting i left it on, is that normal?

I dont know if i need a new compresser, or a blower motor...im clueless any help to steer me in the right direction a!ppreciated .TIA
~DIRTY~

 

There are several things that could be wrong.... most likely a loose/corroded connection in the HVAC controls.

I don't think you will need a new compressor though

Try this... When you put on the AC, open the hood and look to see if the ac clutch is engaging. If it isnt, the problem is electrical. Try wiggling the Low Pressure Switch on the side of the accumulator. If that doesn't work, trace the wires and eliminate from there.

 

If the A/C comes on when you hit a pothole (tough way to cool off ) it is most likely a loose wire or a sticking A/C relay. The A/C relay is on the firewall right next to the fuel pump relay IIRC and may even be the same part # as the fuel pump relay.

Yes, there will be some air flow from the vents with the controls off - perfectly normal.

 

thank you so much guys im gonna go outside and check it again, ill post back if i have no luck.

 

ok well im back, tried wiggling some wires around but nothing happened. when i pop the hood i can see the a/c clutch engaging, and then a few moments later disengaging with a "click" is there maybe a fuse somewhere i have to replace? is there a fan that pulls air into the cabin and maybe thats on the fritz and needs replacing? wadda ya think guys.

 

~bump~

 

The A/C system has a pressure switch that disengages the compressor if the freon pressure is too low. If when the system does operate, you get cold air, it could just be a bad pressure switch or the system is low on freon.

 

i would like to thank you all for helping me out, i beleive its the blower motor and im going to autozone to pick up a new one.

 

guys, i joined this thread late, but where exactly are the AC clutch and pressure switches located that are referred to here? my AC will sometimes come on, run for a bit, and then fizzle out and not come on again. had my AC system installed in early summer, so i'm sure my freon level is good. i need to find these two switches if anyone can point me in the right direction. looks like one is on the accumulator. the other? thanks.