overheating on a 05 pontiac grand am with the 3.4l. I just changed the thermastat and it is still overheating and the heat blows cold what are the possible causes?

Also when i Squeeze the top radiator hose it feels as though it doesnt have any water in it?

Could be an air pocket in the system or the water pump is bad. Did you drain out all of your coolant recently for a radiator change or anything?

Low coolant. Need to bleed all the air out of the system. Air pocket in the cooling system will cause this issue.

If refilling your system and allowing any trapped air to escape does not fix it, I would suspect your water pump has died as "Reelin68" has suggested.

watch out for a head gasket problem. thats sounds like the head gasket is going out. i wouldnt be driving it too much with it like this you can blow the engine.

and if its the water pump the car will continue to over heat until one day when you are driving all the water will dump onto the ground from the pump. oops. and youll see steam under the hood.

Did you ever figure out the problem

Yes it was the answers above. The bleeder valve started to leak causing air to get in system. And when changed thermostat. Naturally depressurized system making worse.