Originally Posted by GradyService

Platinum 4's (As welll as Platinum 2 and standard platinum) are resistor type spark plugs. I have learned the hard way that, for a MB, use regular, non-resistor Bosch Super (copper) or standard NGK plugs. I had Platinum 2's in my 560, but, under the advisement of my dealer and this forum, am removing them and replacing with the Bosch Super.
Good Luck, and God Bless,
Dave.