Why does my 04 cruiser temperature gage show hot when still goes down driving on 2004 Chrysler PT Cruiser

At stop lights gage goes up back down when driving

Asked by for the 2004 Chrysler PT Cruiser
It is not uncommon for the temperature gauge to rise a bit when the vehicle is stopped, before the cooling fan turns on. If the gauge is going in to the red, it could be that the electric cooling fan is not working properly.