I have a question about the A/C system in a 2005 mazda 6. The A/C system works ok when the car is moving (accelerator pedal is being pushed) but when the car is idling the air coming out of the vents gets warm. I hooked gauges up to the A/C system and tested pressures at 1500 rpms. High side pressure was over 320 psi and low side pressure was around 60 psi. Normal pressures according to the workshop manual are around 213 psi high side and 14 psi low side. I tried removing coolant from the system until the pressures were in the normal range. I was able to get the pressures into the normal range by removing coolant, but then the A/C wouldn't cool at all. When I put coolant back in to replace what I had taken out (making the pressures really high again), I found that as before, the system would cool, but only with the engine revving, at idle it would not cool. Any thoughts?

 

check alternator to see if won't give enough jiuce? Actaully, I am trying to add freon to mine, do you add it to port closest to dash/firewall? Seems to be the one. I actaully added too much, and I think it wouldn't cool, let some out, then okay. Need to add more though, wantto make sure is right port.

 

Check & make sure both cooling fans are running any time the A/C is on. If they're not both running, this could explain the higher than normal high pressure readings.

 

AC clutch going bad..?