The engine number just like the chassis number has 14 numbers.
The 102.985 is the type of engine, w/o the last 8 numbers you might get the WRONG part as many changes have been made since 1985. IF you have books then look in the back of the service book, all of the DATA card info is there including the complete engine number.
Of course since you car is a 1993 it will be the LATEST of the engines made.
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)