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

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.
http://www.aveoforum.com/forum/attac...d-imag0324-jpg
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..
http://www.aveoforum.com/forum/attac...d-imag0325-jpg
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!

I think its the Brake Booster, The service manual is kinda vague, but thats the only part with a hose, ill check mine tomorrow, but i think mine doesn't have anything plugged in either.

Edit, it looks like the fuel pressure regulator, later on in the manual it says to remove the fuel line and has a drawing of that.

Thanks for replying! The only thing is, i looked on autozone.com and the fuel pressure regulator sits inside the gas tank... and its not the brake booster... i just dont know what exactly it is and i dont know if it not being plugged in to anything could be the reason why sometimes my rpms will jump to 3000 rpms and stay there at idle...

i just looked at mine, i don't even have a connector, but i pushed on the rod on the bottom and it made a vacuum noise and liquid noise, so im assuming its fuel related.

Hmm maybe it is, i dont know lol But thank you very much for the information! I just wish the aveo had a diagram labeling every part in the engine compartment to make this stuff easier on us! Haha

This is Vacuum hose belong to the VGIS ACTUATOR tank the one you market on the red circle

Please see and read the attach files for proper installation



Attachment 6101Attachment 6102


If you need more information about your Chevrolet Aveo I will be more than glad to you help, I got a lot of experience with Chevrolet Aveo Engine specially with engine (F16D3) E-TECH II

Thank you! so what exactly is the actuator for? I guess what I'm asking is what does it do and should there be anything connected to the spot in the back?

It changes the intake path, at 4500 rpm, at low rpm the path is long and narrow and at high rpm its short and fat, it maximzes engine power and effinciency

ohh, okay thank you! should i be worried about there not being anything hooked up to it electrically?

Look at the technical drawing posted by clinton snow, then you should understand