Not knowing what has been done already I doubt if THIS forum can help your problem! However the only items that control running conditions on these cars are air mass(sensor), engine temp, & the ME fuel computer. ALL of the M119 engined cars run well around here. Quality of fuel is important & in many areas the fuel quality is suspect because of emission LAWS.
Running poorly cold can be a result of oil viscosity that is too high, what weight oil is used by your service center?
MERCEDES Benz Master Guild Technician (6 TIMES)
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190E 2.3 16V ITS SCCA race car (sold)
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