gbbeil

Thanks for the replies. Silveradosid: My AC does get very cold. Operating correctly, does the temperature sensor/switch turn off the AC but allow it to blow warm? Seems like if it was too cold, it would still allow some of that cold to blow into the cabin and stop the compressor for a while. I guess I do not understand how this works. Muddkatt: How were you testing it? Could a code reader tell me what is wrong?

After starting in the morning, AC will blow cold for up to an hour. Then, it gradually warms up to what seems to be outside air temperature - California heat. After anywhere from 10 to 30 min. of this and then it will blow cold again for about 10 min., then hot, then cold.... When it first begins to get warmer, an immediate sense of increased humidity is felt and the an extremely faintest of odors can be sensed that could be called musty, but again, it is extremely faint. If the truck is turned off for about 10 min. or longer (haven't tried shorter), it will blow cold immediately but begin to warm up after about 10 min. then repeats the cycle. Auto shop first recharged system which only made the cold time last longer at first but cycle continues. Could the blend door actuator be acting up on its own by opening for outside air then closing all on its own? If so, are there more than one blend door actuators on the Silverado? Greg 2000 Silverado 4.8 L V-8