Spark Plug Replacement - M271
Pop the cover off....loose the bolts that hold the direct-coil.....unplug the coil....pull them out.....put spark-plug socket in there and turn it counter-clockwise....That's it
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M271 has a very unique plug, so make sure you get Bosch FR-6-MPP-332......DO NOT get something else(eg Platinum, Fusion, Bosch+4, E3, etc.) Otherwise, you'll trash the engine!
Thanks a lot.

Thanks,
Andy
If I remember it correctly, M112 has twin-spark.....so you need 12 plugs total.
Bosch FR-8-DPP-33 is the one you need.


The plugs I pulled still looked pretty descent; the #3 and #4 plugs were dry and had just black and the center was a normal tan color. The #1 and #2 plugs had some oil on it and when I looked way down into the spark plug hole, I could see that the piston tops had oil on it. When I pulled off the coils for the #1 and #2 there was a little oil in the coil tubes as well, so I may have a leaking valve cover gasket. Hopefully nothing worse.
I will pull the plugs again in about 5000 miles to see how they are running.
The plug remove and replace took a total of 45 minutes with a break.






