Engine temperature gauge

If it does this multiple times during the first ten to fifteen minutes, then gradually becomes steady, it can be solved if you insist by replacing the thermostat with one with a tiny bleed hole. Most import engines come with that already. It takes a while for the heat in the coolant to migrate over from the temperature sensor to the thermostat. When the thermostat opens, the coolant circulates, and cold coolant from the radiator rushes in, makes it up to the thermostat, and causes it to close again. This repeats until all the coolant is warm. The bleed hole lets the hot coolant flow over to the thermostat quicker.