2000 Toyota Corolla Smell of fuel

Every morning when i start my car in my garage so that the engine can warm up a very very strong smell of fuel starts to come all the way inside my house. I dont know whats wrong with the car and my car sounds very heavy although it has a stock exhaust. Even after the car has warmed up and im driving around and if i get stuck in traffic or something and i put my car in neutral and rev my engine a little i can smell the fuel in my car ( that is when my windows are rolled down ).
Parking lots any place where my car is stationary i can smell fuel. I dont know if its my exhaust that is the problem....
ANYONE HELP!!