Lack of oil led to lack of turbo

[skyhigh350]

Hey guys.. The car im dealing with is a 91' 6 bolt 4g63 turbo awd. A friend owns it now and he was driving me home and his oil pressure was low/gone same with the boost.. I told him to stop but he kept going about 1 more mile.. His car has been consuming oil/leaking out of the turbo oil lines. Any how, today i pulled it all off, the turbo looks good from what i could see on the outside.. I put new gaskets on and lines. The manifold to turbo housing was loose and i tightened that hoping to fix the problem of no boost. Anyhow its done and has no boost now, it goes from -15ish or 20ish to 0. It dogs, and is throwing out clouds of smoke.. Is the problem the turbo? Idles fine and feels like it has the same power it had before the turbo kicked in. Could a turbo throw oil into the intake because there is alot going through it.. Thanks guys...