Maybe someone in this forum can answer my q....Do I have radiator fluid running through the core at all times, or just when I turn on the heat....I'm curious as to whether I should expect the misfire that everyone gets on top of #4 from the leaking heater hose or clamp or whatever it is...But I live in FLA and never use the heat, maybe I've used it twice in two years. The other 99% of the time it is on ice cold setting for AC...

 

Coolant flows thru the heater core all the time.