Can anyone tell my what the normal operating pressures are for the high side and low side a/c lines with the compressor on and the car at running temperature, and with the compressor off and the engine cool?

I have been getting some very disturbing pressure readings from my low side line, above 150psi all the way up to 800psi (according to the Ice Cold Air place not far from my home.

If the low side is too high does that mean the compressor is working (pressurizing the system), but there is a blockage, or could the compressor still be bad?

 

sytem cold, engine off=both should be near 100psi

engine running A/C on=low should be approx. 20-30psi, high approx. 200-300psi(depending on ambiant temp)

 

thanks, any idea where the blockage could be if the low side is reading 150 psi with the a/c on and the car at temperature?

*edit* I just checked the low side pressures again and with the car off and after it had cooled completely the low side was reading 100psi, when I started the car and let it warm up and turned the a/c on the low side pressure increased to 150psi.

I can't seem to get the same pressure reading out of it twice...

I don't have the correct fitting so i can't check the high side line pressure.

 

Are you sure the compressor is running? When mine isn't the low side reads near 200 psi, but when it is running it reads about 40 psi.

 

a/c performance chart

 

as usual shoebox you are a font of great information, thanks a bunch

 

question.. is the high side really low? if the low side is that high and the high side is pretty low then you probably need a compressor.


make sure that the clutch is coming on and lemme know what pressures you have both high and low. I can tell you whats wrong with this info



EDIT: can I ahve a little history on whats been done to teh AC system? there isn;t a hole lot at all that can cause a blockadge. usualy when that happens the low side will go REAL low and usaualy pull into a vacuum.