it is for sure the fuel pressure regulator vac hose

once i took mine for a spark plug change and when i got it back I took a look around for any shortcut he may have taken and i found this port the same as yours....

i took a deep look around and found the end of the vac hose sitting on top of the trans... it was the Blue stripped hose

I just got it (with a lot of time, it was sooo tight there) and reconnect it back


96 NJ SWB 3.5 pajero(Bone stock)
84 NA Hi-roof Pajero(also Stock)