1991 190 E 2.6 running warm

[just-n-time]

Well gang my wife has this 91 and I notice that it likes to hang around 90c also heats up to the point that it dose not like to restart after say 30 min. rest at the store, it will lite up then die then turn over for 20 seconds befor it takes off, The radiator is original equipment and the car only has 82000 miles on it, would you recommend replacement of the core or have it boiled? thanks JNT

[Mercedes Guy]

Could possibly be the thermostat, but I'm not sure if that would explain the starting problems.