Could u take another photo of the nipple? Kinda hard to see where it is.
I first thought it was the brake booster hose, but u say its not.
On the upper intake manifold there is 3 nipples on one side and i think 4? on the other side. If the nipple in your picture is the bottom nipple on the firewall side of the UIM it is supposed to go to the oil injector splitter. The splitter has 4 nipples, one for each oil injector and one big nipple going to the bottom nipple on the UIM.

that nipple is already plugged. i read online that it was to the acv, which has been blocked off as i stated. so the vacuum plug mustve come off. i think from driving the car with that plug missing, i severely flooded the engine.