Inaccurate temp gauge readings?

2018 NISSAN SENTRA
60,000 MILES • 1.8L • 4 CYL • 2WD • AUTOMATIC
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KYLERODNEY
Some days my temp will be normal some days my temp will overspike past hot
Oct 15, 2025 at 3:03 PM
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STRAILER
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It could be the coolant temperature sensor is shorting out, or the sensor is working and the thermostat is getting stuck. Does the engine overheat? if not lets swap out the sensor to see if that fixes it, or you can use a scanner to check the reading when the temperature gauge is maxed out to confirm the failure. Here is a guide to help and the location of the sensor in case you want to change it out. Check out the images (below).

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Oct 16, 2025 at 2:07 PM
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KYLERODNEY
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No the engine doesnt overheat.. no check engine lights either
Oct 16, 2025 at 3:55 PM
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STEVE W.
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I would check the connection on the temp sensor as well as it sounds like it is intermittent. When it is making contact it reads correctly, then when it opens it sees the high resistance and the gauge spikes.
Oct 16, 2025 at 4:51 PM
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