Cruise control issue

[BBB]

I have a 92 f250. When I plug vacum into the servo it goes wide open throttle. I unplugged the electrical connection, and same thing. I bought a salvage servo and does the same with or without plugging in.
As soon as vacum is applied it goes wot. Any ideas?

 

[KansasIDI]

I have a 92 f250. When I plug vacum into the servo it goes wide open throttle. I unplugged the electrical connection, and same thing. I bought a salvage servo and does the same with or without plugging in.
As soon as vacum is applied it goes wot. Any ideas?

I also have this problem. No idea why.

 

[BBB]

I am connecting into main vacum line off the pump. Is their any way it should be regulated down? Just thinking.

 

[BBB]

After some digging. Their is a vacum switch on passenger inner fender well with 3 wire plug that must limit the vacum. I plugged it in parallel with the vacum going to Cruise and now it works. Still some issue with the accel and coast but doesn't pin it's ears back every time I put vacum to servo.

 

[mf7lakes]

That thing right dare don't got nuttin' to do with the cruise control

 

[BBB]

Really what is it ? I also ran lines to the vacum tree that is up by the evaporator. Any explanation of how this all works would be great. My Cruise works now. So I thought I figured it out.

 

[tradergem]

I think that is the low vacuum switch for the brake light?