In my case wife complains all the time of gas "fumes" in my garage.. BUT since the sky is not in the garage, it usually comes from 5 gallon fuel containers that I have for the emergency generator, OR from one of my fuels holding lawn equipment, you know, mower, edger, weed whacker etc etc..blower..

BUT if it in your case coming from the Sky, that MUST be addressed ASAP, pop the hood and make sure it is the culprit, check the ground under the car for leaks..fuel will leave a mark on the ground, pass your finger over any "dark" spots and smell it....