Though the engine doesn't turn over, do you hear the starter engaging?

Worst case scenario, it is possible that oil pressure dropped low enough that the engine seized and now the starter can't break it loose. But I can't imagine that happening - it would be pretty rare. You need to make sure the battery and starter are healthy.

Alternatively, you can put a breaker bar on the crankshaft bolt and attempt to turn it over by hand. Make sure you go clockwise.

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08 W251 R350
97 W210 E320
91 W124 300E
86 W126 560SEL
85 W126 380SE Silver
85 W126 380SE Cranberry
79 W123 250
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