You are talking about part number 15 right? Looks like it is part of the EGR. More Information for AIRTEX / WELLS 4F1838

If you have another car, go grab a new vacuum hose from an autoparts store. Cut to length and reinstall on the car. I would replace any vacuum lines that you have removed, they can develop small cracks that can be hard to find later on. Easier to just replace with new lines not, also they are not expensive at all.