My 05 Civic EX has got me thinking if the head gasket needs replacing??
But,... no coolant in oil, no white smoke from exhaust, no air bubbles in radiator coolant when cap is off, engine temp is perfect,
I have not done a compression test nor have I done a combustion leak test.
Problem is the coolant reservoir keeps filling itself right to the top!! Could this be a bad rad cap? It looks fine, there is pressure in radiator when I open rad cap.
Installed a new thermostat also. Could there be an air lock in the cooling system? Or do I face the reality that its the head gasket??

Maybe start with combustion leak test? Fingers crossed !!
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