i got a 2004 bmw CI and it started over heating so i replaced water pump thermostat lower hose then the electric fan the coolant and it still over heats
If fan is working right,and you have replaced all you said,you may have a bad radiator,or you have internal engine issue.
Make sure that you bleed the cooling system, so there are no air bubbles, there is a bleeding screw on top of expansion tank, you can see procedure on youtube.
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