Is my thermostat broken?
#1
Is my thermostat broken?
Hey All - I have a CEL and after about 10 minutes of driving, the temp on the car is still below 80 degrees C.
You think this is the common thermostat failure? I haven't had a chance to get the code pulled yet, been busy with work. Just hoping it's something cheap![Smilie](https://mbworld.org/forums/images/smilies/smile.gif)
Thanks,
Tim
You think this is the common thermostat failure? I haven't had a chance to get the code pulled yet, been busy with work. Just hoping it's something cheap
![Smilie](https://mbworld.org/forums/images/smilies/smile.gif)
Thanks,
Tim
#3
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Join Date: Sep 2013
Location: Finland, Europe
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W203 C200CDI
The problem could be partially jammed thermostat. Usually the temp. wont be anywhere near +80c with a completely broken thermostat. You can get the OEM 92c thermostat for about $70 / 50eur even from the dealer.
I had similar issue before and it took me over 1h of driving to go above +80. I replaced the main thermostat and the little thermostat (CDI engine has 2). I did not have any warnings/error on my onboard computer though.
I had similar issue before and it took me over 1h of driving to go above +80. I replaced the main thermostat and the little thermostat (CDI engine has 2). I did not have any warnings/error on my onboard computer though.
#4
Super Moderator
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If you can't read Benz codes the thermostat code would be a P0128
Thermostat starts opening at 87 deg C & should be fully open at 90 deg C. If thermostat is not operating correctly the car will run colder than this.
Thermostat starts opening at 87 deg C & should be fully open at 90 deg C. If thermostat is not operating correctly the car will run colder than this.
#5
I'm a college student and will have to drive home Monday, which is about a 3 hour drive before I can fix this. Will that damage the car or is it ok as long as I don't rev it too much?
Thanks for your help,
Tim
#6
So I got my replacement part today, quick question:
How much antifreeze am I going to lose if I don't drain it before I replace the thermostat? I had the antifreeze replaced when I bought the car only 2 years ago and don't want to have to drain it all out.
Tim
How much antifreeze am I going to lose if I don't drain it before I replace the thermostat? I had the antifreeze replaced when I bought the car only 2 years ago and don't want to have to drain it all out.
Tim
#7
Super Moderator
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Strage, my post disappeared that said you could drive the car. One or two litres should be OK for top up.