could somebody tell me what the black wire that touches the key lock cylinder does in my 96 stang gt

 

I don't know for sure, but do have a couple of thoughts.
Most black wires are ground wires.
There should be no wire that is just 'touching' something... it should be connected to something.
Is your car auto or manual?

 

on the outside of the key lock cylinder there is a black wire with apiece of metal attached to it that sticks through the lock casing and touches the the lock cylinder it is automatic 4.6 liter you have to take the cylinder out to see it i would appreciate any help

 

I'm thinking automatics have something that won't let you remove the key when it is in gear... maybe something to do with that?