My A/C is good and cold while I am rolling but if I sit stopped for awhile it starts blowing hot air. I am thinking there is a problem with the compressor clutch. I think it slows down too much at idle. I had pulleys on but took them off and noticed the problem when I had the pulleys. The issue has not gone away minus the pulleys. Anyone can advise me?

 

Oh yeah is an 03 Screw XLT with 5.4.

 

The clutch either works or it doesn't. The speed is dependent on engine RPM. Sounds to me more like an undercharge. Is it cycling fairly quickly? It shouldn't.

 

Check the clutch gap.

 

I had an 02 with the 4.6l that did the EXACT same thing. I popped off the plastic shroud covering the radiator and to my suprise there is another radiator behind the front one. mine looked like a dryer vent full of lint. I cleaned the lint off of the face and havent had the problem since.