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car randomly overheats on idle

1087 Views 3 Replies 3 Participants Last post by  TheHockeytowner
a while ago my expansion tank just randomly blew up in a drive through, i replaced the water pump and thermostat. every now and then when idling it’ll just start running hot, heat on or a/c on doesn’t matter, hot or cold outside doesn’t matter it has done it in all conditions. could it be the fan is going out and it’s randomly not working?
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check out BMW fan clutch test on youtube. does your aux fan operate?
yes the fan operates and turns on when i turn the car on, turns on when i turn the ac on, but i have not checked it when it overheats because by time i notice it’s overheating i just shut off the car immediately
check out BMW fan clutch test on youtube. does your aux fan operate?
Did you bleed the cooling system properly after you replaced the water pump and thermostat?

If yes, is it filled to the correct level when cold? The only time I've observed the phenomenon you described (temp gauge creeps during idle) was when my car was very, very low on coolant.
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