Engine overheating

I checked the antifreeze last night and it was bone dry. I filled it up to the fill line in the tank. After running it for thirty minutes, the engine temperature stayed right in the middle. For a brief minute, I turned the vents from defrost to heat and the heat came out cold for a minute. The heat got warmer and the engine did not over heat. I let it run continuously for an hour and there was no heat issue or overheating of the engine. Do you think the heat went briefly cold for a minute due to the antifreeze running through the engine after it had been bone dry?

I was driving down the highway and noticed my temperature gauge dropped to cold then not even a minute later I realized that my A/C was blowing heat.
What could be the cause of this?
Could it be one thing that causes both?
Or could it be multiple things?
Car still drives great.

Car overheated and shook, then shutoff on me. Diagnostic said thermostat failed. Drove it without the thermostat, still overheated. Unclogged thermostat and still nothing. It starts rough but still overheats. What could it be?

I commute with this car about 80 miles a day. Lately it's been trying to overheat. Sometimes successfully. It has a new water pump which I replaced recently when I did the timing belt kit. It also has a new thermostat and housing/outlet. The system has been flushed and refilled with dex-cool antifreeze/coolant. After all that the car still wants to overheat, but only when doing freeway speeds or going up a hill ect. Basically when the engine is reving or turning more then 2000/2500 rpms. I have to keep the heater going full blast and sumtimes that isn't even enough to keep it cool. I now have the radiator out of the car and I flushed it out with the garden hose. It doesn't seem to be clogged. The tubes that I'm able to see( only a few) don't look clogged. Should I replace the radiator anyways? Or try reinstalling it and see if it helped? Or do you think it could be a clogged cat converter? I appreciate any help. Thanks in advance. Eric

Ok I thought would go ahead and replace just so all the based are covered. So I'll replace it and see if that solves the problem. Thanks again

Engine getting hot it bubbles and then it seems ti boil the water in the expansion tank, the other day I took out
the thermostat and it seemed all right but now she tells me it is still doing it and also I performed a combustion test to see if there was any combustion gases in the coolant and there wasn't and water pump seems to be moving water because I turned on the heater and there was hot air and I took off the bottom hose of the radiator and it seemed to running through pretty good does any body else have a idea. Thank You

My 2004 chev aveo, I was not getting much heat from it all winter. Heater would be on all the way and turned up all the way and I would get warm air then cool then warm. Now when my car idles in traffic, the temperature gage is climing up to the 125 celcius. Is it my theromostat that has to be replace or the heating core.

I have changed the thermostat and housing and gasket. I must have not bled the system correctly because the car it still overheating. How do I bleed the air from the system? Which cap do I take off. The overflow or the actual radiator cap?

My air condictioner was not working well then this morning my car overheated