Ford Repair: heating system - vent stuck open, vacuum hose, air vent

Question
i have a 1990 ford ranger. the oustside air vent is stuck in the open position. where do i find it and how do i close it? is it operated by vacum or electric?

Answer
From your description it sounds like you are getting airflow thru the dash vents at all times, or does it not go into Recirculation mode?

Here are the vacuum hose colors for the various motors. You either have a hose off at one of the motors or a leaking motor. Possible the control head could be failed, but more likely a hose or motor.

Floor/panel motor-yellow or blue
Panel/defrost-    Red
Recirc-           White

If you lost vacuum completely the system diverts to defrost