I have a 99 durango with the 5.9l. Recently while operating the a/c, the air will quit coming out of the vents. If I move the selector to the floor then back to vent, I can hear the doors change position and the air will come out of the vents---but only for a little while, then nothing again. Also, does the cruise operate on the same vacuum control? The cruise will not hold anything above 60mph. I have had the lines checked and nothing appears to be leaking. I live in Phoenix so no a/c really sucks.