Smells like fuel from vents 07 EX

Hi..I have a 07 Honda Civic EX with less than 30k miles.. For about a month now I notice a really bad odor, similar to that of raw fuel coming from the vents while in the fresh air mode... when I put it on recirculate the smell goes away. Took it to the dealer. The complete fuel system and exhaust system was inspected and nothing was found. I was not behind any vehicles when the smell occurred so as not to be confused with exhaust from other vehicles. The smell is still present and I really want to resolve this problem. Any expert advise would be highly appreciated. Thanks


I forgot to mention that I already changed the air filter and the cabin filter behind the glove box..