White Mold

I've quite suddenly developed a white mold bloom on and in my old Buick. It has not been driven in a couple of years and sits in the corner of the garage. My wife is aghast and likens it to the Andromeda strain.
I've moved it occasionally, the last time in May and noticed no mold, so quite sure this is all recent. The garage is only a couple of years old, dry, insulated and tight but not constantly heated. It spread to a floor jack stored under the car but nowhere else that I can see. The other cars have been in and out and seem to be fine so far.
Has anyone else had this experience?
I plan to don my tyvek tuxedo, particle mask and gloves and move the car out for a wash and vinegar treatment. I will clean and treat the garage also. Anything else? Do I dare to put it back in for the winter? Any ideas as to what caused it or how to prevent a recurrence?
Tom

There's fungus among us. Anywhere mold spores find a friendly pH level and relatively stable surface, they'll reproduce, moisture or not.

So change the pH, by spraying with vinegar or baking soda mixed in water, and the mold won't keep spreading.

Wash off as much as you can with detergent and water, rinse, then coat (spray) the surfaces with the vinegar or soda mixture.

Been there myself.
Tom M.

I think a good stint in a sunny place will help, get the interior really dry.

Thanks Tom and Tom. Tom
And Tom, good suggestion about the sunshine, I don't think the stuff likes UV either.