1989 F250, 7.5
Passenger side of engine, very close to firewall and to the left of the blower motor. It is about 2" round and has a very thin white covered wire coming out of it. It has a flat metal thing on the bottom that pivots if you move it. The wire literally fell apart in my hands. In fact I don't even see a wire...just the groove where a wire might go. I can see a picture in my manual of it in some diagrams, but it is not labeled as to what it is.
Thanks...

 

Looking at it closer, it doesn't look like a wire was inside. More like a very narrow tube of some sort.

 

heater box part??? Could be a vacuum line for your HVAC box.

 

Can you get us a picture? I know those old Fords inside, out and upside down and that doesn't sound like anything I have ever worked on before.

 

Hopefully this attaches ok

 

Vacuum operated solenoid for your heater box.

 

What does it do?