rx7 wont stop spewing black!
 

i took off the exhaust at the stock exhaust manifold, due to excessive smoking. My resoning was that i knew i had bad Cats so i wanted to see if they where the reason the car smoked. after unbolting the exhaust my car spewed this BLACK (so black it looked about 5 feet deep) liquid, i checked oil and it was still at the same place since i just changed the oil 2 day prior.

a few times after this i have started the car with out too much smoke, then i cleaned the TB and threw some deepcreep in my vac lines, the car went crazy and started dieing (naturally) so i start revving it and i hear this sound of what i think a car throwing up would sound like.

so i look under the car and there is a puddle like 2'x3' of more black stuff and lots of smoke from the exhaust... my question: is this carbon build up or is something really wrong with this engine?