Overheating trouble

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Jobi-Wan Kenobi

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Anyone ever dealt with engine overheating with extreme cold? It's -30 here this morning and my coolant temperature was climbing past 240F.
 

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Jobi-Wan Kenobi

Jobi-Wan Kenobi

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Maybe what I should do is try taking the temperature with an infrared thermometer on like the thermostat outlet. Because I wonder if that value that's being broadcast is actually correct.
 

OR VietVet

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Sounds like a blocked radiator, faulty fan clutch or a stuck closed thermostat. It is full of flowing coolant, right?
 
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Jobi-Wan Kenobi

Jobi-Wan Kenobi

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I was kinda wondering if it was the thermostat. The fan is moving air and nothing blocking the radiator. Coolant is full. I'm in northern Wisconsin.
 
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Jobi-Wan Kenobi

Jobi-Wan Kenobi

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This is interesting. It's running right now maintaining about 74C which is about 165F (I can't get the units changed to F). The upper hose does have heat. I have a graph running on my scan tool to show the progression of the system heating up and there was a spike where it went to 135C.
 

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This is interesting. It's running right now maintaining about 74C which is about 165F (I can't get the units changed to F). The upper hose does have heat. I have a graph running on my scan tool to show the progression of the system heating up and there was a spike where it went to 135C.
the thermostat could be sticking, if you do not have the part available or handy and need to drive it, you could pull the thermostat and be better off than overheating.
 
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Jobi-Wan Kenobi

Jobi-Wan Kenobi

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I kinda wonder now if the issue is something to do with the coolant temp sensor circuit. Is there something that messing up the value being broadcast over the CAN network. Why would the data when I was running the graph spike? Was there something that was making the gauge read artificially high?

I had a similar issue about a year ago that I never figured out. The gauge was reading about 180F and the value being broadcast matched. I changed the thermostat thinking it was stuck open some but that didn't fix it. The issue went away afterwards though so I never figured it out.
 

OR VietVet

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@OR VietVet the upper hose did have heat. I had checked it before I ran it here when I did the graph from this morning.

@noodlesandsam2 that I'm not sure. I would have to test it.
Sorry, I misread your answer. BUT, had heat and is HOT can be 2 different things. Was it HOT to the touch or just warm/had heat?
 
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Jobi-Wan Kenobi

Jobi-Wan Kenobi

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@OR VietVet it had been sitting for maybe a half hour at that point so it wasn't hot. It was warm at the water pump connection. But the long stretch over the fan shroud wasn't so cold either that I couldn't squeeze it.
 

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