Miata smells like fuel inside

I can smell gasoline inside my 2000 Miata. At first I thought that I might have just overfilled the tank, but I seem to recall having a similar issue with a '96 about ten years ago. I think it was a fairly simple fix, but I don't remember what I had to do and I can't find any reference to the problem online.

Do I need to replace the filler hose or is it something else?

Thanks.

One of my friends had a 99 Miata with the same issue. Fuel leak of some kind obviously don't recall what it was but your paranoia might be justified lol

Pop off the access panel and see if there is a noticeable gas smell. Could be a vent line, fuel return or the gasket for the fuel pump assembly. All are accessible and an easy fix. I'm going with a cracked vent line, but YMMV.

My 99 had a that problem. The fuel filler hose was weeping and replacing it seemed to take care of the issue.

maj75 wrote: Pop off the access panel and see if there is a noticeable gas smell. Could be a vent line, fuel return or the gasket for the fuel pump assembly. All are accessible and an easy fix. I'm going with a cracked vent line, but YMMV.

Are you referring to the access panel in the trunk or the one under the shelf behind the seats?

I think the fuel pump is accessible thru the panel on the parcel shelf.

Well, that was easy, and probably free too.

I removed the metal panel in the trunk that covers the fuel filler hose. Below the connection to the fuel tank, there is a big rubber seal and there was a small pool of oily, gas smelling sludge. It's pretty obvious that with the tank completely topped off, gas was sitting in that near-horizontal section of hose, weeping out past the clamps and accumulating on that rubber seal. The light solvents would evaporate off and the sludge stayed behind. I cleaned it up, aired out the trunk and tightened up the hose clamps, which were fairly loose as the old hose wasn't as pliable as it was when it was new. I think that should take care of the problem. I may replace the hose just to be safe.

The filler hose hides behind this panel and the metal cover behind it (three bolts):

You can see the little pool of sludge below the hose. There wasn't a lot, but it was enough to stink up the interior. Hopefully, a few turns of the clamps will take care of the problem.

Update time:

The car still smells like fuel after a fill up. The easy fix would be, of course, "Don't fill it all the way to the top, dumbass", but that wasn't good enough for me.

I finally broke down and ordered a replacement fuel filler hose, figuring that it has gotten old and brittle and was probably the source of a vapor or liquid leak.

I had a hard time finding the the right part number, as it wasn't as obvious as you would expect on the parts diagram. I called Mazdaspeed, confirmed that I was ordering the right item and they had it in my hands the next day for $31.

FYI, my car is a 2000.

I removed the trunk panel and fuel hose cover and loosened the clamps on the old fuel hose. I should note that the fuel gauge was reading about 3/4 full at this point. If you're doing this, make sure it's a bit lower than that.

This was the first sign that I might be on to something...

The fill pipe that feeds the hose is galvanized but there was a bit of rust at the seam where it was welded. Hmmmm...

When I pulled the other end off of the fuel tank inlet, here's what I found:

Also note that you can see the fuel level just inside that pipe. I got very lucky that it was just low enough that I didn't end up with a trunk full of fuel when I removed that end of the hose.

I'm not sure whether to blame ethanol, age or some combination of both, but it was pretty clear that no amount of clamping force on the fifteen year old hose was going to result in a good seal.

Here's a good look at the inside of the hose ends:

I cleaned the tube ends up as well as I could with gray Scotch-Brite (I didn't want to make any sparks) and then coated them with grease to ease installation of the new hose, help it seal better, and to keep future corrosion at bay.

With the new hose in place, all I have to do now is reinstall the cover and carpet.

I'm not ready to proclaim "Problem Solved", but I have a pretty good feeling about this.

In reply to Woody: Good article! I'm sure most of us learned a whole lot!

Thank You!