1992 Chrysler Le Baron Strange gasoline smell, poor milage

Hello: My 92 LeBaron sends a smell of raw gasoline through the vents at the first complete stop after sitting for less than an hour. After that first stop, though, the smell doesn't seem to be there anymore. It also has been getting rather poor gas mileage. I just bought this car so I do not know if this occurs in warm weatheras well. Any ideas?