I have a 2001 Pontiac Grand Am GT with a 3.4 L v6 and just after it starts up in smell gas inside the car untill I let it out the window. Gas mileage seems normal, 22 to 24 mpg in town.
Check for fuel leaks around the fuel lines, pressure regulator, fuel rails and injectors. If they are OK, check the charcoal canister and hoses. The canister may be saturated, and leaking fumes out of the bottom vent.