Possibly the thermostat is opening and closing with the water pressure changes.
Could be low on coolant also.
An automobile temperature gauge can fluctuate when the thermostat is opening and closing erratically. The temperature gauge can also fluctuate when the ground wire is loose.
Temperature.
The temperature gauge on a car fluctuates because the car's thermostat is opening and closing. The gauge goes up when the thermostat closes and the gauge goes down when the thermostat opens.
low coolant
My Altima had that problem and it was the water pump going out. It started with temperature gauge was moving, but then it started leaking and finally the heater stopped being warm at idle.
A short in the turn signal wiring can cause the voltage gauge to fluctuate. A loose ground wire can also cause the gauge to fluctuate.
In cold weather, the temperature gauge may fluctuate as the thermostat regulates the temperature by turning the heat on and off to maintain the desired level of warmth in the house. This cycling on and off is a normal part of the heating system's operation to keep the indoor temperature consistent.
Potenially a bad temperature sensor or bad contact on the wire connector. Test for set voltage resistance according to temperature.
What are you talking about? My temperature gauge works fine. Though, if it wasn't I would check the temperature sending unit.
temperature gauge not working can be caused by a bad temp sensor in engine, a bad gauge in dash, or a bad fuse
Head gaskets!!
Your temperature would usually fluctuate. But if your car has over heated then there is a chance it may need changing