What would cause my car to hesitate only in drive? transmission is fine. on 1993 Mercedes-Benz 400SEL

My car hesitates in drive but runs fine in park and the transmission is fine. What could cause this problem when the transmission is perfectly fine?

Asked by for the 1993 Mercedes-Benz 400SEL
There could be an ignition problem that only exhibits under load. There could be a leak in the air intake ducting that only appears when the engine torques over when under load in drive. There could be other engine control issues but I'd need more information to have any ideas on that.
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