Hi...

The engine temp. gauge for my W124 93 E320 had been giving incorrect readings for more than 3 months. According to the gauge the engine temperature would never cross the 50 mark, even when it is summer and the external temp. would top 40 Celsius.

Last week I took the car to the mechanic and replaced the part shown in the
pictures (sorry for the quality). The image called 'main' shows the actual part
and the image called 'big' shows the location of the part to the engine. I really do not know the name of this part since I'm new to this, but I am learning.

The gauge started to give more realistic readings but I noticed that the engine temperature is now higher than what it used to be. I remeber that the highest temp. that the guage recorded when I got the car was between 80 -85, and that was in mid summer with A/C on and the car still.
But now after I fixed the guage the reading would easily top 85 with no A/C on and while the car is moving. It is still not summer and yet the reading is high. I suspect the copper washer that came with this part I got. I think it is giving the extra heaT. I checked the oil, water and the radiator has been changed less than 2 years ago.

Any suggestions, help will be appreciated. I wonder if there are any links where I can educate myself more about engine part names.

Thanks

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The part your mechanic replaced is the coolant temperature sensor. Don't worry, your 'new' 85C reading is just what you should see under normal conditions.
regards,
Mark

Thanks Mark for the reply. Could you tell me when exactly I should start to worry, because the temp. will definitely go higher in there is a traffic jam and specially when summer arrives, which is very hot and humid, 40C plus

Regards

Does anyone know the name of this part?

Anyone?

?? Also known as the water temperature sensor.

__________________
Daily Driver: 02 E430 4MATIC
In the family: '03 E500 // '04 ML500 // 64 220SE

That is NOT the gauge sensor ..

Gauge sensor is single pin

http://catalog.eautopartscatalog.com/mercedesshop/sophio/image.jsp?title=Water%20Temperature%20Sender&url=http%3A//img.eautopartscatalog.com/live/P403612281FAE.JPG

Here are the specs for checking it's calibration

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

You can also sub a Radio Shack 1% resistor of one of these values to test the accurcy of the guage I use the 67 ohm for best results.
Or , you can ohm sensor at different temp and make gauge/chart comparisons

Thanks for the info. Arthur

__________________
Daily Driver: 02 E430 4MATIC
In the family: '03 E500 // '04 ML500 // 64 220SE

Tacobell - Relax. It will be normal for the temperature to go up when idling in hot weather. When the temperature gets to the kick in point, I think it's 100, then the two auxilliary fans in front of the radiator come on and cool things down.

Worry, if the needle gets to the red zone. That's trouble.

Remember a cooler running engine is not necessary better.

Steve