My 560SEL recently started having this issue where it will stay running after removing the key. I figured that it was just a worn ignition switch and replaced the whole assembly with a new one from the dealer. Yet, the car will still stay running sometimes. Now, when I turn the key to the off position it will stutter and then rev up like it would if you were to restart it. Almost as if I am inturrepting the power to the engine for a moment and then it continues to run. Everything in the car acts normal otherwise and it only happens sometimes and it is a difficult problem to recreate.

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1998 E320 Wagon

1992 300D 2.5 TURBO

1991 560SEL M119.960

1986 300SDL TURBO

1992 500SL Parts Car

1991 420SEL Parts Car