A/C problems 99 5.0 AWD Mountaineer

[Dchesser88]

Ok I recharged my a/c system yesterday was so excited to finally have air after fixing my actuators. Well I was idling in the driveway and it was cold I went to leave and start driving and it then began to get warmer and warmer until it was almost hot. When I would stop at stop lights or signs it was cold then hot while driving. I also noticed that my compressor would kick on when slowing down. My coolant level is fine vehicle is not over heating and has a brand new thermostat. Please help I'm completely baffled and know nothing about a/c systems also I put in the correct amount of freon according to the gauge.

 

[koda2000]

you're either are low on refrigerant (hard to tell w/out a set of a/c gauges) or it's possible you're having a problem with your WOT (wide open throttle) relay. this cuts off the compressor, when you floor it, to provide max engine power. it's also possible that you have a problem with you low or high pressure a/c switches, which will cut out the a/c if the pressure is too hi or too low. if your under charged (or over charged) these switches are just doing their jobs. i'm leaning toward under/over charged.

 

[Dchesser88]

Well I set the low side charging gauge at the outside temperature and I didn't even get it to where it said it needed to be. I just checked it with my ac full power at idle the low side gauge started at 47psi but now holding steady at 40psi but like I said I'm idling. Do you think that is a good pressure. I also noticed if I keep my rpms below 1800 which is nearly impossible when driving it stays cold an compressor stays on but when I get about that it shuts off then back to original issue

 

[SoNic67]

If your system was "open" before charging - like getting air and humidity inside, charging will not solve the problem. You need to vacuum the system before re-charging it, change the receiver-dryer/desiccator...

When the reading is between 25 and 40 psi with the A/C running, STOP. The system is fully charged and should be cooling normally

The HIGH side pressure is more difficult to measure, the recharge kits have only low side pressure gauge.