1987 F 150 4.9 Liter. Purchased truck in Sept 2011. Had a couple vacuum leaks which have been addressed. One vac line that was broken lead to do hicker on top of duct work / blower motor. As best I can tell it operates a door inside and in front of blower motor.
1. Am I correct in concluding that this vacuum operated device opens and closes that door?
2. What is this device called?
3. Not sure what this thing does but I did have heat and defrost before I reconnected.
4. Since reconnecting (yesterday) got some noise when i was resetting blower / heat yesterday. Got it to stop by just playing with settings. Ideas?
5. Wanted to attach pictures but site ask for URL of pic. Is there way to upload pics from computer?

 

I take it this "do hicker on top of duct work / blower motor" is under the hood in the engine compartment.


It opens and closes the out side air door.

A vacuum motor.

Yes just upload them to photobucket and post the image here.

 

I just had the same problem with my 87 heres the link to the thread

https://www.ford-trucks.com/forums/1...l#post11092414

 

thank you A++++++++++++++++++++++++++