Expert: Skip Bollinger - 10/12/2006

Question
HELLO MY QUESTION IS THAT MY 1991 LINCOLN TOWNCAR HAS A PROBLEM WELL IN THE SUMMER MY MECHANIC SET MY SYSTEM WHERE IT ONLY BLEW COLD AIR BECAUSE HE SAID THAT I NEEDED A PART TO WHEN YOU MOVE YOUR CONTROLS TO HEAT OR AC IT WOULD WORK, BUT YOU HAD TO GO UNDER THE DASH TO DO IT TO PUT THE PART IN SO WHAT I WANT TO KNOW IS WHAT PART DO I NEED BECAUSE I CAN GO UNDER THE DASH TO DO MYSELF BECAUSE RIGHT NOW I CANNOT AFFORD 500.00 TO PAY BECAUSE I AM MECHANICALLY INCLINED TO MAKE A LONG STORY SHORT WHEN I PUT IT ON HEAT NO HEAT COMES THROUGH THE VENTS SO IM THINKING THEIR IS A RELAY OR SOME KING OF SWITCH UNDER THE DASH THAT RELEASES THE CONTROL SO THE VENTS CAN CHANGE FROM COLD TO HEAT PLEASE HELP BECAUSE I NEED TO GET THIS DONE AS SOON AS POSSIBLE THANK YOU AND GOD BLESS YOU.  

Answer
James,
  It sounds like a diverter door or the vacuum pod that operates it is bad. It could also be just a bad vacuum hose. What happens when you move the dash selector from "defrost" to "vent" to "floor", you are operating different "doors" under the dash. This makes the air go where you want it. There is one that opens a door to the heater core for hot air and one that opens a door to the A/C evaporator core. As I said, they are vacuum operated. Again, it could be just a bad vacuum hose, bad diaphram or broken door. You won't know until you take it apart and see what you have.
  I'm sorry I couldn't give you a better answer but I'm a Parts Professional, NOT A Tech. Also I'm sorry to take so long to respond. I was in the Hospital for a short stay and didn't have time to take my name off the list. I hope this helps. If you need any parts not available from Ford, let me know..
  Skip
  HARD TO FIND AUTO PARTS
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