Not sure if my car is running to rich. I have the stainless steel system on it and it looks to me am getting more black carbon then when I had my 2008 C6. What about every one else.?:

 

Yes, the IS's run rich. All in the name of longer engine life and reliability. Lean would yield more power but would lessen longevity.

 

Mine too. It is normal.

 

it happens to the best of us. just keep some napkins in the glove compartment. i have a stack of napkins in there for two reasons: 1) so my wife can pick her nose; and 2) while i pump gas at the station, i walk to the back and wipe the carbon build up on the tips taking no more than 10 seconds

 

It's more from the direct injection that most all the makers are going to now. Research any DI engine and you'll find guys complaining about excessive soot on the exhaust. The nice thing about our engine is that it uses a hybrid port/DI injection system. It uses port on start up for quick warm ups do get it into the closed loop quicker and switches over to DI for the power when warm. The other nice thing about the Port/DI is that fuel actually passes over the intake valves at some points so you probably won't have excessive carbon build up on the valves like some other manufacturers are dealing with right now. VW/Audi have huge issues with this and guys are getting their intake valves cleaned at 50-70K miles sometimes on their own dime. Anyway, don't let the soot on the tailpipes concern you too much.