Need to find out why this has no wire connected to it!

[josefb134]

I am not sure exactly what this is or what it does, but it seems to me like it is a vacuum that controls either air intake or fuel input but it has a little vacuum hose coming from the front of it, its the silver piece that is circled in red if you can see it. Id like to know what it is and what it does if anyone knows.

This is a side view of it and the upper left hand circle is just circling the unit again, and the right hand circle is circling an electrical plug in or something that should be plugged into this. There are metal prongs in the back of the rectangle plastic piece on the right so something should definitely be hooked up i think... I'm not sure why nothing us hooked up to it because i should be getting a check engine light for it or something to tell me what isn't plugged in and giving readings to the computer..

Thank you for your help and for reading the thread! If you have any knowledge or even a guess of what it is, then that would be great! Feel free to comment!