My car began to smoke from under the hood when I was parked and all the antifreeze came out. I added water, then added about half a gallon of antifreeze coolant to it. But the thermostat keeps moving from half to three quarters back to a little lower than half, back and forth. I am taking my car to my mechanic in the a.m.
car overheats when idling and goes back to normal temp when driving.
While drivin in congested area and idling for 20 minutes the water temp overheated amd I stopped to get more water. I drove to a garage where I was told that water pump was OK and the thermostat had to be replaced. I was able to continue with that repair and have had no problems after that, about 14 months ago.
If let sat an run for a long time it will over heat
Replaced thermostat and radiator.