I was replacing the rubber connectors between some vacuum lines in the engine compartment and got a black one loose.

There are 5 vacuum lines, next to the brake booster, that go into the passenger compartment. There r 2 brown lines, 1 green, 1 white and 1 black that go thru a rubber housing into the passenger compartment, I guess entering the car somewhere behind the instrument cluster.

The black line came loose somewhere inside the passenger compartment, behind the rubber housing. This black vacuum line seems to originate at the fuel pump and go somewhere into the passenger compartment.

What does this black line do and where does it connect ?

Thanks for ur input.