Ford Windstar Video
The Windstar is particularly difficult to work on since the plenum box is buried behind the dash. The center control console has to be removed and the glove box fully opened to expose the box and actuator motor for the blend door. The video's below will show you how to get to the motor, remove it, and diagnose problems in the system. On this particular model, we see problems with both the blend door and the actuator motor. The motor failure is usually a stripped gear inside the motor casing. We do have actuator motors available for this model and will provide details on how to purchase on request. The aftermarket actuator motors have the same problem with the range of motion as the OEM motors, only worse. The new motors were geared at a higher ratio to lessen the stripped gear problem. The result, however, is that the motor moves slower with higher torque. This is good for motor operation, but makes breaking the plastic door much more likely. It's just trading one problem for another that turns out to be worse.
We have to make modifications to the aftermarket actuator motors in order for them to meet our standards. We are not in the actuator motor business, nor do we particularly want to be, and produce these modified motors only as a service for our customers. We will provide an actuator motor at our cost with a blend door purchase or a competitive price for a motor only purchase.
Note in the video that we make a cut in the metal frame using an angle grinder. The dash module is built as a pre-fab unit that can easily be installed during manufacturing before the seats, steering, and windshield are installed. The metal framework is built for integrity of the unit when it is separate from the car and being transported and installed on the assembly line. A lot of the work in designing the metal frame is for manufacturing robustness, not necessarily for automobile strength or safety. We leave the option to cut and bend the metal frame up to the customer's discretion and cannot directly recommend making modifications to the structure of the dash. You can examine the cut that we made and decide if you feel that the cut causes safety issues. We left the cut unchanged on our Windstar, but the choice is your's on your automobile. You can always weld the cut or drill holes and fabricate a metal bridge across the cut. The product can be installed without cutting and bending, but it's difficult and frustrating. After doing a number of these, we found it easier to cut/bend to improve access to the plenum box when doing the repair. Ford did not design this system for ease of repair, so it takes a little creativity to make the repair without full dash removal. You can always choose to remove the entire dash if you desire, but the cut and HeaterTreater components are much much easier.