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Q: Temp gauge goes up and down

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The temp gauge in my car goes up and down. I changed the thermostat, radiator hose, and water pump. It doesn't overheat, but the gauge moves over toward the red and then moves back to cool side. I was told my temperature sensor might be out or bad.

A: Hi there. The temperature sensor is the dev...

Hi there. The temperature sensor is the device used to determine the estimated engine coolant temperature reading. The sensor itself is not always perfect. This device sends a signal to the computer and in some cases, the instrument cluster as well. A loose connection or malfunctioning sensor can sway the values and show an improper reading. If you need further assistance, I recommend you have a certified technician, like one from YourMechanic, inspect the electrical components to make sure all the connections are good and replace any failing parts

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