Winter coming, need advice for this newbie...

If you start it up and let it run for 10 or 15 minutes you will
be creating moisture in your engine. You will need to let the
car run for a lot longer so that all parts in the engine are
up to operating temperature, not just the coolant.

I was doing this same thing when WildCat here on the forum
had me take off my oil fill cap. It had milky condensation on
it. From that time forward I quit starting it unless I could
take it out and drive it to warm it up.

Hope this helps.