Mercedes: engine will overheat? 190E, mercedes benz 190e, number search results

Question
I have a 1993 Mercedes 190E 2.3L. After 10 minutes rides, the car temperatures will go up around 100 and the radiator fan will turn on, but it will not turn off afterward and the temperature is always around 100 even driving on highway. I think the temperature should go down after the fan is on. Is there something wrong with the coolant circulation? Is it ok for the fan to be on always? Any help would be greatly appreciated.

Answer
Answer:
Best guess:
* Bad thermostat.  This is what I always replace first.
* Bad fan clutch.
* Bad radiator.

PART NUMBER SEARCH RESULTS WITH PRICES
Vehicle 1993 Mercedes Benz 190E 2.3
Part: Thermostat Kit
 Note:  87 degree
G4001-14603 Thermostat Kit Wahler IN STOCK $23.14  
 
G4001-14603 Thermostat Kit Behr IN STOCK $20.72  
  
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