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Overheating was bad thermostat

2486 Views 9 Replies 7 Participants Last post by  Machtig
I reported in an earlier thread that the beast experienced overheating and that I got a "check coolant" message. Turns out that the whole thing was caused by a bad thermostat. The car probably wasn't actually overheating, as the coolant had not boiled out the escape valve in the radiator cap even though the temperature guage rapidly climbed into the red. It was merely a false reading. However, fixing this took flying in the parts (thermostat and O rings), a wait of a week to ten days, and $500. These thoroughbred cars can be temperamental and expensive machines, but I guess we knew that when we bought them.
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I reported in an earlier thread that the beast experienced overheating and that I got a "check coolant" message. Turns out that the whole thing was caused by a bad thermostat. The car probably wasn't actually overheating, as the coolant had not boiled out the escape valve in the radiator cap even though the temperature guage rapidly climbed into the red. It was merely a false reading. However, fixing this took flying in the parts (thermostat and O rings), a wait of a week to ten days, and...
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What?! There is way too much bad info running around in here. The thermostat is purely mechanical. When water gets to 79C it begins to open and continues to open until fully open at what temp I am not sure. However, if it gets stuck, due to whatever reason, and its hot outside, the car will overheat, which is what it sounds like happened in the OPs case. The temp sensor merely "reads" coolant temp and reports it to the guage on the dashboard(and the ECU, but that is neither here nor there in this case). If only the coolant temp sensor was bad, the OP got taken for a ride. However I strongly suspect the car overheated. Just because it didn't overflow does not mean you did not overheat. ALWAYS trust your indications.

Did the mechanic replace the temp sensor? Did he tell you the line about it likely not overheating? If he did, I'd find a new mechanic because he is either a liar or is clueless.
 
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