The air conditioning system has extremely high suction pressure of 250 psi and discharge pressure…
Air Conditioning high side pressure
I started having issues with my A/C system a while ago. It was not very strong in general and when I drove long distances, after about 20 minutes, there would be on and off cold air.
When I connected a manifold, the values with the engine off were fine but once I turned the engine on, the low side would immediately go into “retard” while the high side would read about 145 psi.
In the past, I hit an object in the front of my car, so I knew that the condenser might have an issue. It was a little bent and with a thermometer, I saw a significant difference in temperature in areas right next to each other, therefore I replaced it. However, since it still gave me the same readings, I also exchanged the compressor. The clutch had been working (actually constantly running) but I never heard it humming.
Still having the same readings.
What else could be the problem? The TXV, evaporator or orifice tube? How can I test them before attempting to replace?
Anytime you replace the Air Conditioning compressor the manufacturer recommends that you flush the entire system. The manufacturer also requires that the orifice tube and accumulator/expansion valve be replaced at the same time. If this is not done the manufacturers warranty is void. With that in mind if you are getting a higher reading there may still be a restriction.