co2?

Sorry,
not an internet fix,
needs a tech who can read and understand live data,
specifically the long term and short term fuel trims would be what I'd look at first.

1/4drive
January 2015

It is very difficult on modern motors now as there are no adjustments you can make to help lower these readings but I would make sure all your filters are in good order,plugs are in good condition and would probably try a fuel conditioner and maybe an intake cleaner, I don`t know what sort of running you do but if it is a lot of town driving that may be part of your problem also.

cdc
January 2015