Having problems with your 1999 Ford Expedition ?
Within the past year I had the heater coil replaced and the blender door because I had heat in the back but not heat in the front.. Afterwards I had heat and air for a few months only. Now I only have a little heat coming from the tiny vents at the top of the vent but nothing coming from the vents.No heat either. Cold air in the back. Also I only get the tiny bit of heat after it has idled for 15-20 min.
It sounds like the blend door motor is failing or is stuck. You could go to mitchell1diy online to diagnose this and for the instructions to remove the dash. Plan on spending a day or two on this if you have never taken a dash out before.
You might want to have the temperature door actuator checked and make sure it is actually moving.Also check the heater hoses and make sure they are both hot to the touch.If only one is hot then you need to replace the heater core.If they are both hot then your problem is in the temp.actuator or the control head itself.You could have codes checked in the hvac control module.This could give you an indication of what is causing the problem.If there is a door or actuator that is not performing correctly there should be a code in the module.Not all service shops have the scan tool that will read the hvac module codes.This will not turn on any lights.Hope this helps.Good luck.Let me know if you need any more help.
Repair Help & Product Troubleshooting for 1999 Ford Expedition
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