My 1995 C280 seems to be running hot, the gage shows above 80c but below 120c(red mark). The fans only kick in when I turn on the AC. Should the fans kick in even with the AC off once the car hits a certain temperature? I replaced the thermostat already no change.
Any help is appreciated.

Thanks
SG

 

Fan kicks on with AC.
Also, high speed fans come on at 100. This is normal for your car to run at 100 (esp in hot weather, traffic, AC on, etc). Even 110, is ok... but anything above 110, I'd get a little nervous.
Have your radiator flushed; might help the prob.
Also, change the coolant, using MB coolant only! And do a 40/60 ratio of COOLANT to WATER (60%).

Good luck!

 

I have the same problem with my 94 C280. I've replaced the thermostat, replaced the radiator, and still no help. It's never boiled over, but it's running way hotter than I'd like it to be. Any suggestions? Could it be the coolant pump? Timing (i'm getting the check engine fault code p0170 Fuel Trim)? Or maybe the car's just old...it has about 127k miles on it. I'm out of ideas...thinking bout just taking it to the dealer to have them diagnose it.

 

Just for the record... Mercedes claims that coolant temps of 110 degrees in extreme conditions (high ambient temp, traffic, AC, etc) are within normal operating range.

Unless it's cruising above 110, and only partially at 100, I wouldn't worry... the system is running as designed. ANd just to be safe... keep a good eye on the coolant temp gauge!

 

Well, My 1995 C280 runs at around 80c for the first hour of driving with no problem then it goes up and then from there just keeps running hot.

 

I know it can be a bit disturbing... however, the temperatures you describe are nothing but normal. I hope you will feel reassured; those are acceptable (and common) coolant temperatures.