I was driving the engine light came on reading Heater Circuit o2 sensor and shortly after engine started running hot. I have replaced the thermostat, water pump, and heater sensor. Engine still running hot. I have had the air bled out of the lines and it runs fine until it cools down and starts again it instantly runs hot. While driving it usually mellows out and stops halfway but when the vehicle stops it goes back to hot. I don't know what else to do. The last person that looked at it advised that it had too much coolant in the radiator and drained it but would that make it run hot? PLEASE HELP.....WANNA SCREAM !