I have no front heat
Just changed the thermostat (it was stuck open)
Now have rear heat, but still no front
No popping sounds from actuator, but can hear it moving if I listen carefully while under the dash
Can see actuator turning blend door shaft when looking up from under the dash
Ocasionally when switching the air to the front panel, the air will switch on it's own to defrost and then moments later come back to the panel, especially noticed that it will move to defrost if I have the fan on high and then by lowering the fan speed, it will move back to the front panel?Any ideas?

Does anyone have pictures of what the blend door looks like and/or have a link on how to get at it to see if it is warped (without removing the entire dash)?

Is it possible that the shaft is turning but the actual blend door is not moving inside or is it all one piece?

Also experiencing the P0174 codes...it was difficult to locate the parts for the fix, but I had to go outside of Ford because they wanted 4x the price I got at Lordco! Thanks for the posting with pictures; I will attempt to fix it next weekend.

I have had similar issues with my 2000 SE. I had a short somewhere with one of the locking actuators that caused the blend door to go bad and had to be replaced. I could hear a clicking noise of the blend door trying to move and finally it died altogether.

Can you elaborate on where the short was and did you fix it or get someone? If you did get someone to do the work, how much did it cost?