over 10% of my emissions is straight CO alone. (legal limit is one something) and ive got 975 ppm? of HC - legal is 220. I want to sell this piece soon - '91 prelude . There is a tiny, tiny bit of black smoke is that fuel or oil? Today i updated ignition, air filter is clean, i added fuel injector cleaner, no leaks in exhaust. Anything else? If its piston rings, then screw it, but yall got any other suggestions. I can get the inspection hooked up, but i dont want to have to sell it for $500 less because it is smoking.