I noticed today while driving our new C350, the temperature gauge stays above the half mark, around 90C to be exact.
Coming from some BMWs that used to overheat, this just brings back A LOT of bad memories and makes me worried.
Is this normal?
Thanks.

 

Mine is just about two weeks old and its right about there also.

 

There was another thread about this and I am pretty sure the consensus was that 90 is the norm. My C300 runs at that temp and so did my '05 W203.

 

That's exactly the temp it should be running at.
Quite a few threads have been posted about this.
It seems that MB just calibrates their temp gauges this way.
The same behavior can be noted on most models including the W203s.

Nothing to worry about.

 

Has anyone noticed that there is any variation from this 90'C when the situation changes eg high ambient temp, higher engine load ie towing , climbing slowly up a steep hill? I my experience with the 220CDI ,no matter the circumstances , the engine coolant temp stays at 90'C. This have not been the case on previous cars I have owned.
The only reason I can think of is that the radiator & cooling fan have plenty of capacity unlike other cars.The thermostat must also be well designed. John.

 

Which cars were these previously?

I've owned cars since MY98 and never seen fluctuations of coolant temps on steep climbs. Not even on track days.

However, I do believe that because many problems in cars during the manufacturer warranty periods come from the cooling systems years ago, that most manufacturers put in better thermostats and cooling systems.

 

I have owned cars since 1964 & each ones temperature guage has varied under different ambient & load conditions up until our first MB.
John.

 

This info is taken from the Manual. If yours is running at 90 then it's well within the range so nothing to worry about.


Coolant temperature gauge
The coolant temperature gauge is in the instrument cluster on the left-hand side. The coolant temperature may rise to 120 under normal operating conditions and if the concentration of antifreeze/corrosion inhibitor is correct. The coolant temperature may rise to the top end of the scale at high outside temperatures and on long uphill stretches.

 

Benz have a normal operating temp of 87-105C.

The one important thing to note is that the new generation of V6 and V8's have a electronic thermostat so the engine ECU can vary the operating temp between 80-110C depending on ambient conditions. When it's cold outside then the engine will run at a higher operating temp to help keep oil temps up, if it's hot and you need high engine load then it trys to regulate 80C to maximise performance.

Expect the temp gauge to move around a bit.

 

Yes, we've covered this ground before...a lot...

We have extensive experience driving this car in extreme heat - ambient temps well over 100F. It never budges from 90 C. It will occasionally drop as low as 85 C in colder weather, but not for long.

(No, this is not BMW redux...but I understand your concern if you're coming out of a BMW.)

Anyway, not a problem - this seems to be a common misconception based on the way the temp gauge is calibrated - 90 C is where it will settle, notwithstanding the fact that this is past the "midpoint" of the gauge.

 

I have a 2001 CLK 55 AMG and I was having this same exact problem as well too! I was getting little worried about my car. It was close to 80k on it. I live in michigan. When I turned on my car, after few minutes it will be at 80 but then fluxuates little higher or lower but around 80. I was going to take it to the dealership and they would probably ripped me off. Now, I see there isn't really nothing wrong with my car. I appreciate everyone help and happy for this website!!!