Camshaft adjusters and timing chain wear
M270Adjuster noise from around 60,000–70,000 miles; chain wear around 80,000A rattle when cold that was not there last year.
The camshaft adjuster solenoids wear and start to make themselves heard cold. Mercedes fitted modified actuators from 2014 which last longer. The chain on this family is a genuine wear item rather than a lifetime one — plan for it rather than be surprised by it.
Parts this needs
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