running rich

[pdqcrx]

have a 1990 crx si bone stock. It runs rich but does not code. leaves black soot on the bumper and burns your eyes. I have tuned it up with plugs and such. Funny but it runs great don't skip or nothing just really rich. Could the o2 be bad but still not code???

 

[Taco15]

i would start at the 02 sensor. Is there any backfiring? if so replace your ect sensor while your add it. its only like 25 bucks. If your ect switch goes bad it tell the ecu to dump mad amounts of fuel. i had a similar problem. replaced it and havent had a problem since. good luck