Hello I am new to this forum, but just recently I bought a Honda civic 96 with a b16a2 swapped into it. The swap itself has 98k miles on it I just have a few questions. On start up the car smoke a bluish/blackish color and when i high rev it spews out what seems to be black carbon. My brother put his hand near the muffler and I revved it @ 3k quickly and his hand was literally black. The car runs and pulls fine though it seems like it also has an exhaust leak though because you can REALLY smell the fumes inside the car that distinct exhaust smell. In general I am pretty new to Hondas as I got the car today I just hope this isn't something too serious I figured the check engine was something like the fact it has no cattylic converter, or maybe a bad sensor. YES i did use the search before anybody asks lol, but I figured my scenario might be slightly different. It also does this once the car has warmed up to good operating temperature. Any insight or help would be greatly appreciated thanks!

 

Black smoke is usually an indication of running rich. Is it running the stock ECU or has it been chipped? Also, try finding out why check engine light (CEL) is on, that will help us narrow down your problem. Sounds like a bad O2 sensor causing the CEL and causing it to idle/run rich.

 

Sounds like the cars running rich, does the rear bumper have a black Soot on it and is the car getting bad MPG?