Originally Posted by tjspiel

Perhaps a very miserly car under ideal conditions burn that little gas in an hour. A typical car will burn 1/4 to half gallon of gas in an hour. Maybe even 3/4 of a gallon for something large. A school bus could burn as much as gallon. And as your chemistry magic showed burning a gallon of gas produces more than a gallon of water !

Of course an individual car doesn't sit at intersection for an hour but you have many cars idling at busy intersections all throughout the day. Of course they don't just idle either, they accelerate as they move on, burning more gas and producing more water than they would if they were idling.

You were convinced that any water vapor immediately rises up and out of the way. I showed you a picture that shows that is simply not the case. As they say, a picture is worth a thousand words and that same picture shows plenty enough water to cause problems.