Can someone tell me what this is?

[manifoldsrme]

It is on the passenger side fender well area of my 1987 T2 Daytona. There are 3 vacuum hose connections and right now none of them are hooked up. Car still runs fine and passed emissions with no problem. So what is it, and why do you think it was unhooked? I am trying to "clean up" the engine bay because it is a huge mess of vacuum lines. I plan on installing a vacuum block, but am wondering if I have to incorporate this back in. I figure I should know what it is before I decide. Anyone?

[moparfreak3]

That is your barometric pressure sensor on mine the map sensor sits right above it. The nipple sticking up in the air goes to the map sensor nipple and the one sticking out towards the engine goes to manifold source. The one sticking out towards the fender is just a vent.

[manifoldsrme]

Thanks. Is this something I need to hook back up? It seems to run great without it.

[NAJ]

Yes it is needed.
The Baro Solenoid is used by the controller to block vacuum to the Map Sensor so it can update Barometric Pressure readings for proper Fuel and Timing control on Turbo vehicles.