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

Rookie cbe0621eac06868b3efe0d8d1d3611e23c60d3114864ea2ec19a68cfbd3eebab
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?
(1) Answer
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.
If you want to find a specialist, here's a directory link for you: