Most later cars have t-stats that run at 92deg so i was prepared to say you were about right. I looked up the t-stat for that motor and its only a 80 deg.
Based on that the car should probably run 190 or so. The temp reading on a t-stat is when they start opening.
Be sure your auxilary fan is working. Change the t-stat. Check the flow in the radiator. Thats the order we usually take if we suspect a motor to be running over t-stat temp without stress.
Bosch Master, ASE Master, L1
33 years MB technician