Not knowing what model car!
Most MB's run between 80C & 100C and aren't overheating until 115C. NEWER cars seem to run right around the 100C mark as most of them have a higher temp thermostat.
Higher temps help with "MOST" emissions. NOT NOx
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)