Their is a black hose that runs alongside the hose that connects the banjo bolt to the switchover valve. It sits in the same clip as that hose. It's black. It runs to the top of the three way hose fitting....The Y fitting had an allen wrench pushed in where the black line is supposed to go. I took the allen out and put the black hose in it's place. It causes the transmission to not change out of first gear properly. When I disconnect it and put the allen wrench in the y fitting the transmission works fine again. What' my problem? What is that black vacuum line?