Truck a/c system will blow cold air sometimes usually for about 20 mins. then will start blowing hot if you cut the a/c off for about 20 mins. it willl blow cold again mechanic before me supposedly changed an orfice tube filter and the compressor I have had the system down when i replaced the heater core in the dash and had to break the evaporator out vaccumed it down and recharged to correct charge
Aug 12, 2010 at 2:45 PM