Air conditioning only cool when idling
 

Hello,
Have a 2002 jetta 2.0 litre that has an AC problem.
At engine idle, cabin temp is a cool 50 degrees F. As soon as engine RPM's are brought up above idle(1500 rpm), the in cabin temp goes all the way up to 75F. Once back to idle, the temp will restabilize to 50F. AC pressures are 50 psi low side, and 113 high side at idle when all is okay, and creeps up to 80 PSI low side when problem occurs and restabilizes back to 50PSI once back at idle. High side stays at 113 PSI with or without the problem. All condenser fans are operating, and no noises from compressor and low side to expansion valve is cool before, during and after problem. High side from expansion valve is warm. Cabin vent controls all work the vents and move the air(whether warm or cold) properly between defrost, face, feet, face and feet etc...
Has anyone experienced this problem and potential causes?
Any info, would be greatly appreciated.
Thanks:rolleyes: