I have a 95 Explorer with 139K miles. The heater fan started blowing very hot air and then luke warm air. At the same time, my gas mileage fell sharply. The symptoms sounded like a stuck thermostat. My mechanic replaced the thermostat but that did not solve either problem. We ran the self diagnostic test on the automatic temperature control and got an error code 25 indicating a blend door problem. The mechanic removed the glove box and said the actuator is moving but the blend door may be stuck or broken. My question is why would the blend door failure cause my gas mileage to drop? Are these two unrelated problems or is there another explanation?

 

I have the same thing going on with my 97 EB the heating system works one day then blows nothing but hot air the next. My milage is around 14mpg and i noticed that at 60mph the engine is at 2700rpm isnt that a little high?
lets keeo bumping this thread up untill we recieve some helpful information.
thanks

 

Slerhman, it sure does sound like you have the classic blend door problem. I can not see, if that is truly it, how it would affect your mileage though. Maybe your AC is on all the time now since it can not properly control the temperature in the cabin. Having the compressor on all the time could affect mileage. I would still be inclined to believe that they are unrelated.