Why Mini stinks. And I've put up with a fuel smell inside the car for way too long. In fact, when I park it in the garage my habit has been to leave the boot lid open, because if I leave it closed the entire car ends up with an odor of gasoline inside. So it's been an annoyance, but I found a way around it.
I finally decided to fix it. I thought the odor might be coming from the fuel tank vent hose. But I verified that was not it. So today I drained and pulled the tank out and I discovered a discolored boot floor from what must be the world's slowest leak. Just enough to produce a gasoline odor, but not enough to do anything other than stain the paint under the tank. It was completely dry there.
Next step: New tanks are very expensive, so I'm going to try and restore and seal the tank with the POR15 fuel tank kit. Has anyone here ever used that product? From my research it looks like meticulously following the prep is the key to getting it to work. Should seal up any pinhole leaks or seam leaks.
I've used POR15 and it bonds really well with good prep work. Definitely wear a respirator with organic vapor filters! Aside from the need for good degreasing and etching to make a successful application; POR15 is also susceptible to UV degradation. Though the fuel tank would unlikely need any topcoat to protect it.