2001 Pontiac Grand Am.... Is it the thermostat?

[Brown Pit named Blue]

A few days ago, my car started overheating. I can drive for about 10-15 minutes, then the gauge is all the way in the red zone and the little light comes on. It is full of coolant.
Also, yesterday, I was parked but had the car running. The temp gauge went all the way to the red and the car started idling very high. Then it stopped. What could be wrong?

**When I drive a little faster, it seems to cool down, but goes right back up when I stop.

Thanks in advance.

 

[wde3477]

It could be the thermostat. Could also be the electric fan not kicking on. Lesser possibilities are a failed water pump or a blocked radiator core.