E420 Temperature Range
 

My 420 seems to run very cool. Seldom above the 60 bar or about 140 degrees.

In stop and go on a warm (hey, it's Seattle) day it may briefly nudge the 80 bar, but not much higher. Drove south to VanWa a couple weekends ago and it was between 40 and 65 the whole time. I checked engine and radiator and both were well with in what I would call normal operating temperture.

Is this a "problem" or should I worry about world peace in my spare time?

Thanks

Mine used to run cool... so my mechanic decided to change the thermostat.

Also... possibly... the probe that checks the engine temp and reports it back to the guage might be faulty.

<<Also... possibly... the probe that checks the engine temp and reports it back to the guage might be faulty.
>>

Here is the test info for that...

60C-110 ohm
80C-67 "
100C-38 "

I had this same problem with my E420. It would usually run at 40-60C on the highway and might get up to just under 80C when in town. Replacing the thermostat fixed it (82C min warmed up temp). Engine wear and fuel consumption are significantly increased when the engine is run cold. I would recommend you change it ASAP.

Chris

How hard is replacing the thermo?

Had a similar problem . . . .
 

but it read just a little low. After removing the tstat, it would not close all the way; so there was a bypass path which made the car warm up very slowly.

You should replace the tstat and check the resistance in Dalton's post to see if the sensor is bad. If ok, then it's the tstat.

It's a bugger(!) to change at least for me: it located near the rubber hose (the short one about 4"). The hard part is getting that hose back on.