Re: 84 300SD - Cool AC from front vents, COLD AC from rear vent. Why???

The reason why the defrost vent is open all the time is because the actuator
for the defrost vent is the most used actuator... every time you start up
the car, the defrost vent shuts... every time you turn off the car, it opens
up.

To fix this, you need to replace the defrost vent actuator... which is
located right next to the glove box.... you have to remove the glove box's
box and then you can see it right on the side on center ... very easy to
replace and cheap... like $35.


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