Thermostat set at 180
Today’s the first time I saw temp shoot up to 240 for a few seconds and immediately went down. Is this normal to happen?
Idling it occasionally climbs to 200 and then drops down.

 

What type of thermostat, inline or oem style?

 

inline

 

it sounds like you have a thermostat element without a bleed hole, check that and report back.

 

sorry for late response. It does have a bleeder hole on top.

Would cold temps cause the high temp spikes?

 

No, it shouldn't. If it happens consistently you might have a failing element, that or a failing sensor. Suggest you pull the element and run it a week like that.

 

240? You have a bad thermostat.

 

There was a recent poster on Facebook who had a bad sensor, I have had one as well. They start acting flaky. Check it with an IR gun. I keep a pen ir thermometer in the console so I can check actual temps if I ever get an excursion.

 

Interesting, meaning the temp is OK but the reading is bad on Nanocom? Definitely possible. Yes !

 

I will be order a new thermostat and replacing it. Hopefully that is the issue. Car idles at 180 and slightly below. The heat spike happens quickly but drops right away. Hoping nothing major.