Klaus, You're absolutely right the guy could have given a little diagnostics to help but many people just don't seem to be able to use google.. I'd have to guess that black smoke out of a gasoline engine freaked the guy out and he posted. A quick google search on what causes black smoke followed by a brickboard/google search of why the engine would run so rich as well would give him the information. Follow that up with a check on those components and checking the codes in the car to see if anythings coming up and he's probably solved the problem and/or narrowed it down to 2-3 things...

It looks like he's doing a head gasket repair job on his other car which is a little alarming.