Unfortunately you could possibly have a problem with your blend door actuator.
(The door is not moving in the direction to allow the air from the heater core to enter).
I has been a long time issue with both Explorers and Mountaineers. I do not know why Ford/Lincoln/Mercury has not resolved the issue over the years.
It is very expensive to repair, not for the needed replacement part but for the labor involved.
($1000 - $1200) - It is ridiculous but "absolutely" true. It is a "BIG" job.
There "is" a short cut which involves cutting a hole in your heater core box to gain access to the blend door actuator. If it was me I would do it without a doubt as long as I had a warm & dry place to do the work. As usual the cold weather is here and it is the time for all the B.S. To take place. If you are not subjected to the winter conditions or do not mind the harsh conditions and you are interested in the "quick fix" just let me know and I will get the information to you.
Sorry for the bad news.
Sunday, November 15th, 2009 AT 11:09 AM