Found out that the left temp dial (drivers side) controlled this stepper motor. The motor worked fine, but as I held the motor in place and turned the drivers side heater dial, I could feel the motor straining to turn the valve past the valve limits, which controlled the air flow. Not sure how this happened??? Anyway, I took the stepper motor apart (picture) and manually turned the brass looking guide so it aligned properly with the valve it mates up to. Now it works fine, the valve opens and closes as it should. Now to get the stepper motor fixed in place as the plastic has broken.. but thinking come sort of "C" clip or tie-trap may do the trick.
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