Temp gauge starts at high when it's been left off for the night in the cold. And remains at high when driving but moves a little more, as if it was reading cold going to normal. But from high to pay high. Coolant level was fine
My car has 238000 miles.
My car has an automatic transmission.
It sounds like you may have a faulty temperature gauge or a faulty temperature sensor. As you may know, there is a sensor that measures the temperature of the coolant that relays this information to the computer which then sends this information to the temperature gauge. When this sensor is not working properly, you may notice in erratic or inaccurate reading as you have described. I would recommend having an expert from YourMechanic come to your location to diagnose your temperature sensor.
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