2002 f250 keeps dying.

I have a 2002 7.3 f250 powerstroke. When I try to
start it it'll run for about 20 seconds then die, it
won't start back up when I crank it over, even when
I push the gas a little when cranking it it's like I'm
not pushing it at all, the rpms don't run up or
anything. And the wait to start light doesn't come
on. I plug it in every night like I'm suppose to, the
only problem I see with it is with the ICP scensor.
The pig tail on the ICP scensor is messed up but
that shouldn't make it die like that.