My brother has a 2004 premio registered in 2007. I was looking under the hood and found that a pipe was removed from the top left and a screw had been inserted into it to stop the flow of something. In my opinion that tube needs to be inserted into the top of the box. Now I don't know what this box does and if it should be out. So, I'm wondering if some expert can help me identify what the box does and should I have it put back like the way it was?
Pic attached 
