Stuck Flap or a bad stepper motor would cause this. Are you getting the air on the floor? That is where it will end up otherwise. Is this a 94 E320? I don't think they made them in 84. ha ha. Go to our website, click on tech stuff, on that page you will find instructions in pdf format on testing your climate control system. Should get you started! I think a 94 has that controller, if I am wrong let me know. Good luck!
Brian

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Brian W. Heitman

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