Check the tail pipe where it extends beyond the rear bumper. You are probably pulling the fumes through the trunk.

I'll not point out the fact the 200D is slow it can't get away from its own smoke! I also question your use of the term "high speed". Never seen it applied to a W110 200D except when it is in "free fall".

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“Whatever story you're telling, it will be more interesting if, at the end you add, "and then everything burst into flames.”
― Brian P. Cleary, You Oughta Know By Now