Wondering why my A/C is not cold anymore. If the A/C needed to be recharged, would it make a hissing sound in the vents like it is doing in my car? I found a couple of threads, but they did not say much. Can anyone help me with this problem? Should I go and purchase a refigerant charge meter? Is there something more that is wrong with the A/C? THANKS!!!!!

 

I'm not the ol wise and knowing with AC but is the hissing constant or just when you turn the switch, the controller that switches the vents goes off of vaccum from the engine, so you will always here a little hiss when turning the ****, if there is a vacuum leak you will here it all the time and this may not switch open the vents or get the AC going. This happens to me every once in a while during the coldest nights in the winter, all I would here was hiss and barely any air pressure. You could run up and get one of those gauges as you mentioned, this will let you know if its leaking out or if its all gone. I found one for 16 bucks (Napa, Murrys) autozone 19 bucks) Have you listened for any hissing inside the engine bay?

 

First off, thanks for the reply. Anyhow, the hissing comes on, only when I turn the **** to A/C, yet it stays on constantly. I am familiar of the hiss when it is turned on initially, but it didn't stay on like this does. From the engine bay, I do not hear any hissing, though I took off the panel under my glove compartment and could hear it hissing there. Tomorrow, I plan to get a refridgerant guage to test it. So, typically, if there is a vacuum leak, will there be A/C refridgerant left? Let me know what you think. Thanks!!!

6/23/03 - I added some leak detector, leak sealer and 14 oz. of refridgerant...there is only a slight change in temp. At least now it blows out warm instead of hot air when it is on the coldest setting. I can't figure this out. I don't believe there is a leak b/c I still have alot of pressure in the system if I open the valve on the low pressure side of the A/C. Any ideas? Also, are there any recommendations as to where I should get my car checked out if I can't find the problem myself? Thanks!