That is a COMMON 16V problem! 99% of the time the problem is the air flow position sensor! Have replaced at least 20 of them for that exact problem.

MB part number 000-074-23-14(complete housing w/sensor) with a list $675! takes 2.5-3 hrs& requires several other parts

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MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
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44 years foreign automotive repair
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190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
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