2005 Chevy Silverado LS. The A/C will blow while the truck is moving but not at all the way. When I come to a stop the cold air stays dormant in the vents. Sometimes the A/C works like once a week. Also, If I'm driving and the cold air is barely coming out of the vents, I crack the window just a hair and it blows a little harder. I had the resistor replaced over a year ago. Can anyone advise? Thanks in advance.

 

Sounds like your fan isn't working.

You would need to troubleshoot the fan and the controller.