WHEN SET TO HEAT ON VENT, HEAT DOES NOT FLOW LIKE IT DOES WHEN IT IS BLOWING COLD AIR. WHEN THE HEATER IS PUT IN BI-LEVEL POSITION IT BECOMES EXTREMELY LOUD AND SOUNDS LIKE THE AIR CANT GET OUT WHEN PUT IN HEAT SETTING. WHEN IT IS EXTREMELY COLD THE CAR DOES NOT HEAT PROPERLY. HAVE HAD THIS PROBLEM LOOKED AT 3 SEPARATE TIMES, 1ST INCIDENT TOLD THAT THIS WAS NORMAL, SECOND SAID THEY "FIXED" IT AFTER A MELTDOWN (SMELLED PLASTIC BURNING) IN THE HEATER CONTROLS, NOW SAYING THERE WAS A TSB RELATED TO THIS PROBLEM THAT THEY WERE NOT AWARE OF AND WILL FOLLOW IT ACCORDINGLY. IF NOT, WE ARE SEEKING HELP VIA LEMON LAWS.*AK