Does it find hot ample surrounded by a vehicle (in summer) beside the window rolled up to exterminate adjectives the germs?
Most of the germs yes, all of them probably not,no. it can carry above 140F in a car(up to 178F actually) and 140F is the heat that all commercial kitchens own to heat your food above to destroy 99.9% of all germs. but in that would still be that .01 that don't get kill and there are even a few strains out in that that would not be killed at 212F.
no, solely tempratures that reach boiling point can do that. You cant put a cup of water within the car and see it boil!
The germs and fungi that would be in even the cleanest of cars would love the extra fry and multiply at an extreme rate. The heat that it would lift to kill even the most adjectives germies would totally ruin the plastic and vinyl interior of your car.
Sitting your hermetically sealed car contained by the sun is a much different thing than industrial vehicle cleaning and steam cleaning.