Hi guys... I stumbled on a thread here a long time ago about this topic. Someone posted that there is a seal that goes under the insert in the filler neck that goes bad, and allows a lot of vapor to escape the fuel tank. I have checked all the lines, checked the fuel pump itself, no luck, and the vapor doesn't get in the car, it is just outside the car close to the fuel door. The problem is that I can't find a part number or a diagram of the alleged seal so I can replace it. Anyone else ever had this issue? If so, how did you fix it.
Sikkaflex (or similar)...... A smaller opening is fitted in the filler neck (for unleaded fuel) to comply with ADR's and a petrol proof 'goo' is used as a seal. Sometimes it's not done properly (or not at all), redo it and your problems are over
I had a problem which was solved by changing my filler cap. I know it is good now, because when I take the cap off to fill up, there is a vacuum that sucks air into the tank. The problem you are describing could also be caused by a filler cap seal. While you are checking for a hole in the seal, do you know for certain that your filler cap (Nissan OEM) is good.
what QLDZDR said re vacum suck I had same issue removed solid filler tube from body to tank leak was in area of the filler hole reducing sleeve inserted to comply cars here in oz had it welded in place by engineer (not welded while in place ok) THEN reinstalled tube good luck
Here's the thing... North American cars don't have that type of insert in the tank. It smells like it is coming from underneath, out of the wheel well. I got under the car tonight and looked around, and it appears that it may be the vent/overflow hose that runs from the filler neck to the tank. Anyone ever had to change one of those? If so, will I have to drop the tank to do it?
I FOUND THE LEAK!! And what a total pain in the ass. I kept thinking it was something down lower because i wasn't smelling it in the car, just outside around the gas door. But when I pulled the fuel pump cover off, I could see the dust was gasoline mud. I ran my finger through it and sure enough, it smelled like gas. Both lines on the top of the tank, the feed and return, had small splits in them. The feed line had a screw clamp on the end that connects to the hard line, and the screw was pointing up, and regardless of how I tried, it wouldn't turn. So I just bypassed it, and ran a long piece of FI hose from the top of the tank down to the hard line under the car. The return side wasn't bad because it had a spring clamp on it. I wonder sometimes if the Japanese people who built these cars did some of that shit on purpose ya know? Anyway, I should get a lot better fuel economy now. I was only getting about 200 miles per tank, but I bet 25% of my fuel was leaking out.
