77 K5 - What the Heck is this Part II - Mystery device in engine bay

[ZombieK5]

I removed the AC Evaporator and the big black case yesterday. During that process I came across another mystery device. This item looks like a small mailbox. It has a tiny vacuum hose connected to one side that runs into the firewall. There is also a thicker hose that seems to connect to the fuel Pressure regulator (pretty sure that is what it is) that is installed on the passenger side valve cover.

Ideas anyone???

Photos attached. Yellow arrows point to hoses. Also used yellow dots to show the hoses to make them easier to spot.

 

[Wes Harden]

Vacuum resevior. doesn't look like the original which is ball shaped and bolted to fire wall above fan

 

[ZombieK5]

Well, guess that will be going bye bye.

 

[paratrooper307]

If you aren't running HVAC then you don't need it. Just make sure you don't leave any vacuum leaks!

 

[Big Ray]

Wow! That does look like a mailbox...