clewis

Recently the A/C in my car has started acting up. I have an 85 IROC and it's been retrofitted to 134A. I turn it on the "max" setting and it begins to work like it's supposed to. Once I start to move, it still works okay and blows between 48 and 50 degrees. Then, all of a sudden the air coming out of the vents starts blowing warm, somewhere in the neighborhood of 60 degrees plus and smells like a freezer defrosting. After a few minutes, it starts blowing cold again. At first I thought it might be related to the throttle position because it seemed to do it whenever I let off the throttle, but after closer examination, it does it both when I'm on and off the throttle. I know the compressor is supposed to cutoff whenever the throttle is wide open, but that's not my problem here. Could it be that it's low on freon? If so, doesn't that mean there is a leak somewhere? Short of installing dye in the system, is there any other way of finding the leak?

justadba

sounds more to me like you might have a vacuum leak problem...when you open the throttle, you are losing vacuum and it is causing the opening and or closing of actuator doors inside your system....

Arntzman

when you retrofitted the system to 134a, what parts did you change? The pressures that 134 opperates at are different than r12. R134a will work in a r12 system, but sometimes at low engine speeds (like idle) the low pressure cut-out switch will turn off the compressor resulting in the air blowing warmer. I think you need to either add more 134a, change the cycling switch on the dryer to one off a 134a system or change the orifice tube.

I haven't converted the system on my Camaro to 134 yet, but I did on my 87 ford ranger. I had the same problem you are having when I'd stop at stoplights, the air would blow really hot. I had to replace the low press switch on the dryer with one off of a 93 crown vic (has 134 stock). solved the problem.

-Dave