Im a newb w an N16 non-turbo/non-JWC automatic w a heavy soot/carbon on the tailpipe issue,
I understand many have a carbon issue w the DI, but from what Ive gathered by lurking is mine is not dirrect injection...but is my vehicle HIGH COMPRESSION?
It's so hard for me to sort out w so many engines, turbo, supercharged and na etc all R56.
W the compression question, Im getting at, do I NEED high octane or not??
Ive only filled up 2x since i got the car, once with recreational non-ethanol 93 and the last with Sunoco 91. Ive wiped down the tailpipe detailing tue car weekly and notice a reoccurring soot/carbon buildup each week, unlike Ive never seen, even with my heavy carboned 150k trade in.
Im also familiar w decarboning w additives such as seafoam, B12 as well a water injection...so Im not afraid, just trying to understand a few things to plan my attack.
Just filled up w Sunoco 91 and added 1/2 a can of Berryman's B12.

Also worth mentioning, the car has 33k and is 2013, I received the car and have driven it bout 1k w the OIL 1.5 QUARTS OVERFILL which I assume is from the 30k oil change noted on the CarFax service report. Naturally Ive drained this off once discovered and have noticed an improvement.
BUT could this be my soot/carbon issue?
Think a sparkplug change is in order as well??

If yall could clue me in on some of these details, Id greatly appreciate it...I dont really wanna waste any money aa tires are in ordee soon too.

Thanks! And Id like to say you have a wonderful community here, Ive quite enjoyed reading and learning about my new car!

 

My wife's stock 2013 R57 Justa with 35k soots the tailpipe as much as my modified 2011 R56S with 83k does. I have also seen many late model cars with sooted chrome tailpipes lately. I really don't know why it happens, but I don't think it's an issue....other than the constant cleaning required. I would always recommend the highest octane fuel available, and not Ethanol enriched fuels. Wife and I always run the best available 91 octane, from quality gas stations like 76, Mobil, or Chevron. Just to be on the safe side, ya know?

 

Look at your plugs!
Have you replaced or checked your air filter?
O2 sensors?

That's a starting point. Back in the old days we would do a tune up, lost art.

 

I haven't done anything but drive and observe...ive had the car only a month now and am still tooling up to do much of anything on the mini. It took me 2 weeks to discover the oil overfill and then drain off the excess.
All Ive done is try different gas 2x, first tank w Gumout Regain(higher concentrate version of techron) and now a tank w Berrymans B12. And now w the B12 my mpg has improved by 3 mpg so far.
Im not ready to do sparkplugs yet, tooling up still and need that 12p socket.
Havent checked the air filter but never would suspect an af for soot on a tailpipe either.
O2 sensor? Wouldnt that throw a code? You mean actual remove and inspect the sensor??
Yeah, tuneups are cool, but im more of an over-maintenace kinda guy...i'll get there when i get there but still in the honeymoon phase and just taking it all in.

Still curious if the N16 non turbo and non supercharger base model is high compression??
Maybe the slower burning additive packed high octane is the issue? I dont know, Im still trying to learn before making any assumptions or spending unnecessary money when tools and manual are the priority.
Im also thinking there is the possibility Im burning off the overfilled oil...but Im open to other thoughts.

 

Its higher compersion, but the soot thing is on the tailpipe is common on Gen 1 and gen 2 MINIs, turbo and non turbo.

Do you have pictures of this soot?