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Stock Problems/IssuesDiscussions related to warranty related issues and repairs, or other problems with the OEM parts and software for MINI Cooper (R50), Cabrio (R52), and Cooper S (R53) MINIs.
Hello! I have a 210,000 mile 04MCS that's started getting significantly worse MPG over the past 6 months and just last week, had a rough idle and P0301 code come up while sitting at a stop light.
I pulled the plug on cylinder 1 which appears to be soaked in fuel. Pulled the other 3 and they look fairly normal after 1 year of use. (See pictures)
So I'm thinking the injector on cylinder 1 is the probable culprit here. Thoughts? Anything else I should look into?
Well for anyone who might have a similar issue, the O2 sensors can start sending inaccurate information to the DME, even without a CEL if the sensors have 100K+ on them. Car was running rich as hell which explained all my issues.
I went ahead and replaced both O2 sensors, put in some new spark plugs, and reset the DME to force it to recalculate A/F measurements. MPGs are back to normal and no more misfires.
