well this is the problem like a couple of months ago my fan had died and it overheated so i replaced the fan, changed the thermostat and changed the water pump and flushed the system and changed the temp sensor. then i flushed the system again and no air in the system now. the problem is that if i start to push the car and drive it hard for awhile it warms up real quicker and it goes above the m in norm on the temp gauge so then i will back off it for awhile and let it cool then it will cool down some then if i do it again it will do the same then. and sometimes if it stays up there then i stop the car the coolant overflows out of the overflow cap. my question is would it be a headgasket or my the radiator is blocked up alittle bit and not cooling it down?