The one thing that got my attention is when you said it happens most often when the car is at idle.
If you were to drive the car at highway speeds for an extended time, would it overheat? If not and it is only happening when stopped or in stop and go traffic, it sounds like the cooling fan isn't turning on.
Do me a favor. When the temperature gauge begins going beyond the normal range, pay attention to see if the fan turns on.
Also, take a look through this link and let me know if anything mirrors what you experience:
Do this and let me know what you find.
Wednesday, March 15th, 2023 AT 9:11 PM