Need some expertise on AC and blowers - 2005 Explorer XLT

[xixo]

So our 2005 Explorer has dual zone climate controls (front and rear). Lately, the front AC only gets cold if the rear unit is also turned on, but whenever we turn the rear air on, there is a relatively loud (heard over the fans and the radio), rhythmic knock coming from inside the driver's side rear panel (all the way in the back). Also, the front air seems to work better while we are driving along - sitting at a stop, air is not so cold. Turn on the rear air - front air gets cold. Turn off rear air, front air warms up. Start driving fast, front air gets cooler (not cold). Thoughts?

 

[BigRondo]

Welcome aboard!

The "knocking" from the driver's side rear panel is most likely the rear blend door actuator. There is several threads on the subject.

As far as the rest goes, hopefully someone with more knowledge than me will chime in.

 

[waskly]

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