2003 Charade with EJ-VE ENGINE, 110k miles.

OK, I'm resigned to the fact that I've got a very sick engine.
The exhaust is emanating a thick soot that leaves a black patch on the ground.
The exhaust gas smells toxic.
No. 1 spark plug is a little sooted up.
No. 2 spark plug is good.
No. 3 spark plug is badly sooted up.
Exhaust fumes being expelled from the dip stick tube.
I suspect the engine is using water.

I think at very least the head gasket hasgone but I suspect it could be worse.

I would however like to know what the diagnostics say. Can anyone tell me what format the diagnostics interface is and where it is?

Secondly, I believe I have two options. Either try to repair the engine or replace it. At the moment I'm swaying toward replacing it, Either way I could do with some written instruction, but I'm at a loss to find any. I haven't found any reference on the internet to a workshop manual for a 2003 Charade or Mira. Has any one else found one?

Thanks, Rob.