1993 GMC Sonoma Q&A

1993 GMC Sonoma Question: what would make the A.C compresser frost over when not being used

it is on a 93 gmc sonoma i am in the the proses of replacing the heater core and was wondering why the A.C compresser was frosted over after driveing but not useing the ac -
Answer 1
If you are using the defrost, then the A/C compressor is still working. Are you using defrost at all? -