Redoing vacuum lines on my 76 360 4 spd f150 with Ca emissions and found a fitting in front of carb inserted into intake with 2 vacuum ports. Both vacuum lines are broke off so unsure of vacuum line routing.
Thanks

 

Identical sensor right in front of one in question.

 

I dont know of your year truck but the 80's had a vacuum hose routing sticker on the radiator support.
If yours dose not you need to find the vacuum routing for your year truck, motor & transmission and for CA smog as it might be different than the other 49 state routing.

Now that fitting is a switch controlled by the coolant temp. If you pull it out coolant will come out.
There are different temp settings for most of that type of switch.
Sometimes there is a temp stamped on the nut side flange or a number on the top to cross over to and the last by the color of the plastic (yellow / green / blue / red / etc)

Now this is just a WAG (guess) that a vacuum line comes from the carb ported vacuum to the switch and out of switch to the vacuum port on the dist.
If the dist. has 2 vacuum ports one on the front is advance and the one to the rear (close to the body) is retard.
I would say this goes to the advance no clue where the other would come from??
This is where that vacuum routing book come in handy.

Do you have to do smog?
If not then run the hose from the ported vacuum on carb to the dist. front port.
Dave ----

 

A lot of newly posted vacuum and emissions stuff. Maybe that will help?
https://www.ford-trucks.com/forums/1...l#post20821317