I had the same problem...I one day was getting horrid gas mileage (8mpg) so I opened the hood and discovered that there was gasoline all over my engine bay and was peeling up paint even on the oil filter. It turned out that my mechanical fuel pump diaphragm had cracked. Since then there has been no smell at all. I also had my gas tank acid dipped and recoated at a local radiator shop for $120.