Earlier 240Ds (including mine) have the clear vacuum exhaust tube to the intake. They changed the pump later on to exhaust into the crankcase, eliminating the need for the tube.

Did you check for oil in the key switch or shutoff line? Maybe the shutoff leaked and everything wasn't cleaned up properly when they fixed it. Or maybe it still leaks - how well does it shut down?

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Rick Miley
2014 Tesla Model S
2018 Tesla Model 3
2017 Nissan LEAF
Former MB: 99 E300, 86 190E 2.3, 87 300E, 80 240D, 82 204D Euro
Chain Elongation References