Fuel Not Burning Completely!!

[solis365]

Hope this is the right forum, please move if needed.

2012 Mazdaspeed 3

I notice that after even just a few days of driving the exhaust pipes get completely caked with black greasy soot. Some of the chunks of soot even fly up and get stuck on the hatch. It seems like the engine is running extremely rich and not burning off all of the fuel. The car is new as of Oct. 6, and has been doing this since day 1 (first week I had it I noticed the soot). It now has 5000 miles and I asked the dealer to look at the problem when I brought it in for service. They say it is not an issue - first they said it could be due to using low octane gas (I don't and never have), and then they said it might be due to winter additives in the gas, but as I said its been doing this since october when it was brand new.

I only run 93 octane gas in it and have never used anything else.
I drive aggressively sometimes (i.e. it gets to redline every now and then)

Any other MS3 owners notice this? Is it just a characteristic/design flaw of the car that every MS3 has, or is mine "special"?

Thanks, second opinions are always appreciated.
BTW the car is completely unmodded, stock ECU of course.

 

[hcbr929rr2]

common problem, search the forums here and at mazda$peedforums.org and you'll see tons of posts about it

 

[Tyrdstorm]

Every bit of my car is pearly white... except the back which is always black. Freaking sucks.

 

[ZPrice]

A few ways to minimize the problem, go to a 5W40 weight oil. Modify the entire exhaust system and tune the car properly thus minimizing the pig rich tune from the factory.

Z

 

[IRONBAR]

comes from the factory running rich a cobb tuner will help mod your afrs to a more nominal standard.

mine gets sooty black too it is also cuased by the turbo but has to do with the engine itself running rich, its normal bro untill u tune it