Hey all, newb here looking for help with identifying a part that is missing a vacuum line. It's under the air cleaner and behind the carb. 1982 22r CA 4x4.

 

It's difficult to tell from your photo but I'm about 98% sure that is the secondary air injection inlet/cutoff valve.
When vacuum is switched on to that port your arrow points to the valve lifts up, air from the air cleaner runs into the air injection pipes, and to the exhaust manifold. It allows additional air into the exhaust after combustion to help burn excess exhaust gases.
Without that port hooked up your valve is closed and won't allow that air in and is going to result in slightly higher emissions.
The vacuum should be supplied from a VSV (vacuum switching valve) but I am unsure which one. The stock emissions/air injection setup uses a maze of connections.

You would not want this valve to always have vacuum. Typically the secondary air injection system engages at startup and idle.

 

I am pretty sure that is the Air Conditioner Idle-Up diaphragm.

 

I would agree, that does look like idle up vacuum diaphragm.

 

Thanks, looks like you're right, it appears to be the AC idle up diaphragm.

New question: truck failed CA smog due to bad ignition timing, and a non-functioning EGR. It looks like the previous owner removed the EGR VSV and VTV. My problem is I now have to figure out which plug the EGR VSV attached to. I also found a plugged vac line that I need help identifying, may have to do with the missing EGR accessories. If anyone with a 1982 truck could chime in that would be helpful, as my VECI label is unreadable, and even if I did know where to plug in the VSV I wouldn't know where to mount it.

The truck is a 1982 4x4 22r with CA emissions equipment.