Calling for AC help.. Experts out there??? I have readings.

[jay3000]

AC cools a little.. Nothing spectacular. Only when I'm driving down the road.. Electric fans blows fine.. I did not check vent temps, but they aren't real low.. Compressor is not noisy..

Outside temp 83 degrees.. It's always humid here at least in the summer..

@2500 RPM

Low side 45 psi

High side close to 400 Psi


With the engine off, the gagues do not equalize.. High side stays at about 225, and low side goes up to about 70 or so..

My wild, poorly educated guess, is that the expansion valve is clogged..

I would love to know what someone elses very educated, expert guess is..

Help.. I'm real close to having a VERY nice car..

Thanks,
Jay

[BobK]

Clogged, jammed or has ice in it. What work has been done on the system lately? What readings do you get first thing after it has been shut down for several hours and then started? Are you still R12?

[jay3000]

I don't have any history for the car.. We assumed that it was r-12, since there were no other stickers on the car, and r-12 fittings only..

I only had use of the gauges for a short period of time.. That's all I have for now..

[jcyuhn]

I'm going to go with either a) really, really badly overcharged, or b) lots of air (noncondensibles) in the system. Both the high and low sides are far too high for 2500RPM readings. If the expansion valve was restricted I would expect high side to be high, low side to be low - something like 400/5 readings.

I'd try evacuating the system, changing the dryer, giving it a thorough vacuum, then charging correctly.

- JimY

[jay3000]

Should both the high, and low side equal out after the engine is stopped?? If so, how long should that to happen???

That would be great if it was just overcharged, and I could suck it down, and re-charge

I would be one happy dude...

[BobK]

Yeah, presure should equalize after a few minutes. Should not take that long. Crazy idea: can you gently whack the expansion valve with a hammer or similar tool? Not sure where it is on your car. Curious if it is stuck and could be "unstuck". I agree with the idea of an overcharge, but I don't think that is the only problem. If there are no R134a service fittings, then you probably have R12. Try not to let that stuff get away. Not to scare ya, but this could get expensive. On the plus side, at least your system does hold a charge

[jay3000]

Guys.. I'm already scared.. I can't keep spending money on this car..At some point I'm gonna have to stop, sell it, and run like hell.

I have a source for r-12 cheap.. I have access to equipmet to recover what I have, and a vacuum pump, and gauges, and a GM certified AC guy..

Knowing all of this, I need a CLEAR direction to to go in.. What would you do???

[csnow]

I do not think you can 'unstick' an expansion valve by whacking it. There are no moving parts. It is just where the orafice gets larger to allow the liquid to expand back to a gaseous state.

[jay3000]

The continuing saga will pick up here..

Help flushing AC system.. Of coures I searched..Please help..