Year: 1998
Make: Volkswagen
Model: Jetta TDI
Engine Size: 1.9
Refrigerant Type: R134a
Ambient Temp: 71
Pressure Low: 55
Pressure High: 96
Country of Origin: United States
I am trying to determine what is the root cause of the slow fading of my A/C cooling over about 4 weeks. When I activate the compressor clutch, I may get mild cooling for about 1 minute and then just ambient temps.
Based on the refrigerant and oil in my gauge lines, I don't think there is any compressor damage. The oil is translucent, clean. Sounds smooth and normal. Condenser and evaporator fans and airflow are good.
I have tapped on the TXV and compressor, but nothing really changes. The low side may fluctuate a little from 52 to 58 psi with a slight gurgling every 30 seconds in the system I can feel if I have my hand on a line. Revving the engine does not affect the pressures.
Ambient temp was only about 71F, high side never got warm...
I suspect the control valve inside the SD7V16, but I am not sure. Opinions / experience greatly appreciated! Thanks in advance!
Scott
control valves do fail but first, recover refrigerant and recharge the correct amount into syste, This way you can eliminate charge as a possible problem. If system works correctly, leak test to find leak.
Thanks for the response. I understand that these systems are very sensitive to the correct charge. I know the system is not overcharged (never had anything added). And, if low charge were the problem, wouldn't my low side pressure at least be near normal or lower? I am trying to determine the cause so I only have to drain and recharge once.
Thanks again,
Scott
Have someone recover and weigh how much comes out. If it was near a full charge, go ahead and replace the compressor. If there was not much refrigerant, find the leak.
First step in system diagnosis; verify charge. Low charge will make you think its something else.
-------------------------
Thanks guys.
We've updated our forums!
Click here to visit the new forum
Copyright © 2016 Arizona Mobile Air Inc.