Over heating problem cant seem to fix it! Help Please!!

[MyJayy]

So 2 weeks ago I decided to change the Idle Cotrol Valve on My 2003.5 mazdaspeed protg. Next day drove the car about 130 miles on the highway, seem really fine. The next morning I drove it around the town it was overheating at every stoplight! over half of where the temperature its suppose to be at! Before I changed the ICV I had no overheating problems what so ever. People have told me that I have air in the system, I flushed the radiator fluid and poured in new fluid. I decided too change the thermostat because it came to mind that maybe it was stuck in the close position, turned the car on with the heater on full blast. Overheated again, the fans turned on way way to late!! I took off the cap off the radiator and turned the car on, The fluid is suppose to disappear when the car starts to warm up but it doesn't. The fluid start overflowing and goes to the overflow container?! That's not right! Ive been squeezing the radiator hoses with the radiator cap off and a couple air bubbles do come out but I was at it for 1 hour and it was not stop so idk if it has a lot of air in the system or im doing something wrong?
Please help me !!!!

 

[xtreme velocity]

Over flow is not really a bad thing when car is running. Try opening the radiator cap and let the car run for a while and just watch the level so it doesnt go out of site, may expriance some overflow but dont worry. let it run for 20-30 min or so. Dont open cap when hot so start this process when car is cold. Also is the heater working in the car currently working? After burping the system again, go out and drive the car and get on it a little and make the water pump move the water/coolant. I have this problem at work a few times and that seems to work. But usually I cant get heater to work, and driving it kinda hard usually helps. But if car over heats DONT continue to drive it. Also does it over heat at a idle or only driving? Usually the coolant will over flow if there is air in the system because the air is pushing coolant out. after air is out of system the level should stay about the same and can see it in radiator.

 

[brandini]

When burping, park pointed uphill, rad cap off, and rev engine to 2k and hold, then kick it and let it drop to idle. Check coolant level and repeat.

 

[hornsfan10609]

The cap may be bad