Air Conditioning problem
1999 Ford Truck V8 Two Wheel Drive Automatic 255000 miles
i have a 99 f250 superduty with a 7.3 turbo. Iv replaced the orfiace tube, high and low pressor switch and the fan blower motor risitor. The problum im havin is it will blow cold then it will get hot for a couple mins then blow cold againe. Then blow hot and stay hot for a while before it blows cold again if it blows cold. What do I need 2 replace to make it work right? And its full with 134a.