can someone please help me out. i have been over heating all day i changed my thermostat and i made sure that i had coolent and that there were no leaks i still was over heating im blowing cold air out of the vent when its on full blast heat it does not overheat at idle only when im driving it. i tried to bleed the system 2 ways one by using the bleeder valve that didnt work so then i tried leaving the radiator cap off and that didnt work can anyone help me?

 

from the sounds of your description u have air trapped in the system. jack up the front end (attempting to raise the bleeder valve above the heater core) and idle your car with the heat on full blast, and the rad cap on, open the bleeder screw and make sure the over flow bottle has coolant in it, and let her run till coolant comes out the bleeder. this is assuming the thermostat is installed in the correct direction.
good luck

 

thank u mint racer finally someone told me how to fix it with out being a ***** i really appreciate it