Does a vacuum hose belong here?

[NewYorkLaw]

2001 busa. I recently changed my spark plugs. Ever since, I cannot maintain a steady speed without feeling an occasional hiccup. I double-checked the gap on the new plugs, the connection on the wires to the boots, and the connection on the boots is snug. I even bought a second set of plugs in case one of the plugs was faulty. It occurred to me that perhaps I missed a vacuum line. I do not see any lines that are not connected, but I noticed the underside of the airbox, facing front, has this hose connection with a flange, that looks like it might be for a vacuum line. Is there a hose that belongs attached to that? If so, where should I be looking for it?

The other two connections have hoses going to them, as do the metallic vacuum cannister in the middle and the skinny vacuum line at the bottom.

Thanks for any thoughts.

Pete

 

[GoldenChild]

That's a water drain hole leave open.. a line goes on that sensor.