Good deal. ..glad that you uncovered your solution!
Tell me ....I am chasing a code of 273d which tells me the cats conversion other than that the car gives no driving indication of a problem...
my 06 X3 M54 3.0 200k on the clock

I've changed the o2 sensors...
Car is new to me purchased as a quick deal...
Would you have any notions as to getting rid of this reoccurring "service engine soon" light?

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