my 2001 sunfire when ever i use the heater it runs about 4-6 marks past the 195 running temp sometimes it goes a littrle hotter when warming up in cold weather , coolant level is fine new thermostat water pump is only couple yrs old thing is when i turn off heat temp slowly goes back to 195 any ideas what to look at next?
Your engine probably isn't actually overheating. It's possible that you have a little bit of air in the system. Running the heat in the car reduces the coolant level slightly, putting the temperature sensor out of touch the with actual coolant temp. Try pressure-purging the system to get all the air out. Check the radiator cap to make sure it's releasing pressure into the recovery tank and then allowing the coolant back in as the system cools.
how do you get all the air out
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