My 2000 explorers a/c compressor works great at idle (ran it at idle for two hours). After driving a few miles compressor quits opperating. High and low pressures are 195 and 40. System evacuated and recharged to exacxt wieght. Pressure switches are fine. Could compressor be affected by RPM or engine heat ( enigine not running hot )?

 

At this point we don't know if your problem is electrical, A/C clutch not engaging when it should or poor connection to clutch or something telling the control, like thermostat in cab, desired temp reached , cut-off. Unless someone has a definite known cause for this problem, this is what I would do. Run a wire from the A/C clutch itself to a test lite in the truck and drive it a while. If the compressor quits and the test lite stays on the clutch coil is opening internally. If the compressor quits and the test lite goes out you now know it is something in the wiring to the clutch which starts from the fuse panel thru inside controls to the pressure switch and on to the clutch. You have your work cut out for you.,,,,,,,,,,,,,hanky