u/Inevitable-Grab-8367

I have a 2008 Chevy Malibu Lt, and recently I noticed when my car sits for 3-4 hours the temperature gauge is a quarter of the way up but when setting more than 8 it starts off at C. I’ve tried to look up causes and what is being told to me is temperature sensor could be going out but I wanted to hear any other opinions. What else could cause this?

Also the car doesn’t over heat