well there is petrol in there... any time door is open your going to smell it obviously.. but if your smelling it while going down the road i would watch under the vehicle while you are pumping the gas.. it is possible the filler tube has a leak and it may even leak onto your shoes while your standing there haha. watch where u put ur feet and watch if anything drips on you.. you really shouldn't smell it in the vehicle itself while driving unless it got on your clothes. but on a flip side... just because u said 2 bolts was missing id recheck that out cause if the filler tube has been removed and wasn't installed correctly or maybe the tube is rusty and they started to replace it... it could be leaking which would be when u fill it up.. remember it might be small leak and it can run down from one area all the way to the other side of vehicle.. if u have ever seen a water leak on a vehicle ud no what i mean its not always in the area it actualy came from haha, so you may smell gas at first from fill ups till it evaporates or goes down low enough to stop leaking.. cause as you drive it will splash around and could hit that leaky spot .. rememebrr fuel is foul smelling and even a small leak will be easly detectable.. so just cause you don't see a physical constant drip doesn't mean some thing under there isn't wet with fuel leaking.... best to crawl under neath and look at the filler tube.... make sure where the rubber part mounts on the tank at is all the way on the tank and there is no holes in it or rips.... the tank itself usualy have a shield so any leaks on it wont be detectable unless you drop the shield or if its physicaly visible... which obviously it will be up high on the tank if there is a leak some where.

its going to be a small leak so all your going to see is a small wet spot with a possible occasional drip but by the sounds of it your leak is going to be on filler tube or up high on gas tank since it only bugs u while its full on gas and when ur pumping it...

Have main dealer check this out as fumes are both dangerous and a health hazard.

Odds are we have blocked vent and fuel is getting pushed into areas it's not wanted eg internally in car. The pipe work and vent system needs looking at.

Most tanks have an evap/vent that runs to a vacuum canister and then to the intake .

If that vent line is broken or detached , gas fumes will come out of it .

Another possibility is a leak in the top of the tank where the fuel gauge sender fits. It may only be weeping when the fuel level is high enough to get to it.

Possibly a leak where the filler tube meets the tank as you say it's worse when the tank is full.

Check under the car for drip patches after filling up or alternatively only fill to 75% full.

With petrol fumes being more volatile than petrol this problem needs fixing quickly.

I have a 2001 MGF, and when I fill the tank up it STINKS of petrol! It smells just as bad with the wondow down and even with the roof down it still smells, even at high speed?? Where is it coming from?

I have checked underneath and there appears to be NO leaks anywhere? I looked at where the petrol tank cover is and found that 2 bolts were missing from the round cover. I put these on and put lots of silicone sealant around the cover, but this has not changed anything??

The engine compartment itself does not smell of petrol, but when you open the door, it just reeks of petrol! It does seem to get better as the tank empites, but always smells?

Does anybody know what this is.....#PLEASE!!

Thanks