Auto Air Conditioning & Heater Repair: Auto Air Conditioning & Heater Problem, auto air conditioning, heating and air conditioning

Question
1992 Olds 98
Heating and air conditioning system blows correct for about 40-45 minutes.  It then will not blow out the vents, defrost or floor.  Blower motor works on all speeds and make a sound as if blowing inside itself.  Have replaced programer, and all misc. components to system.  Where am I going wrong?

Answer
SOUNDS LIKE YOU MAY HAVE A DOOR ACTUATOR THATS STOPS WORKING AND INTERFERS WITH THE AIR FLOW. IT`S ALSO POSSIBLE THAT THE EVAPORATOR COIL MAY BE FREEZING OVER AND CUTTING OFF THE AIR FLOW.TRY THIS,LET IT RUN AND WHEN THE SYMPTOM HAPPENS LEAVE THE BLOW ON HIGH BUT TURN OFF THE A/C SWITCH, SEE IF THE FORCE OF AIR GETS STRONGER.IF IT DOES YOU MAY HAVE A LOW PSI. SWITCH THAT IS NOT CYCLING THE COMPRESSOR OFF AND ON AND IN TURN IT WILL TURN THE EVAP INTO A BLOCK OF ICE..IT DOESN`T HAPPEN OFTEN AND IT`S RARE TO FIND ONE DOING THAT.YOU SHOULD GET ALOT OF WATER RUNNING UNDER THE CAR AS IT MELTS..

GOOD LUCK