[Unicorn123]

OP,

I just had my plugs replaced with OEM @ 77K miles. I was late in doing this maintenance and had the plugs but no time; my local trusted indie put them in for me while was away on travel last week along while performing a full fluid replacement on my car, which I had scheduled.

After replacing my plugs, the mechanic noted a #3 cylinder miss-fire and called me to ask if the car was missing and throwing a code prior to drop-off, which it was not.

Swapping the plugs with the old ones, different ones and the ones I purchased did nothing.

It turned out the #3 fuel injector was encased in carbon build-up and he had to do a full intake cleaning to clear the codes and clean up the fuel injectors. He saw a similar situation on a M235 with 30K (miles) on it that he serviced about 6 months ago.

You may want to check to see what kind of carbon buildup you have, this is not uncommon with direct injection engines like the N55 and B58; this may explain the issues you are seeing. Good luck.