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Trouble filling gas tank

I have a 2000 Toyota 4Runner - when filling the gas tank it takes about 10 gallons then shuts off as if full. You can normally put about 5 additional gallons in but it takes a VERY long time to do so. Any suggestions?

Are you or is anyone who uses the car in the habit of topping off the tank when they fill up? Most modern gasoline cars don’t react well to being topped off. I suspect that is the cause of the problem. It can be other causes as well.

Look around the owner’s manual or on the car for a sticker telling not to top off the tank. It damages the vapor recovery system.

Number 2 on my list is a blocked filler often blocked by the device that is there to protect you from spilling fuel in the case of an accident and to make stealing fuel more difficult. You might be able to see a “ball” shaped object inside the filler hose. If you can gently nudge it a little and if it falls back in the tank, that should fix it.

Another possibility is–believe it or not–spider nests in the evaporative emissions lines. While Hyundais seem to be the most prone to this problem, it can occur in any make of vehicle.

That being said, I think it is more likely that the OP has damaged/contaminated the carbon canister that is the heart of the evaporative emissions system. This takes place when someone repeatedly forces more gas into the tank after the station’s pump has clicked off.

Doint the “click, click, more gas, more gas routine” might be appropriate in the Gobi Desert or some other area where gas stations are hundreds of miles apart, but for those of us who live in the developed world, continuing to fill your gas tank after the station’s pump has clicked off for the first time is…neither necessary nor wise.

If your carbon canister is indeed contaminated, you can expect to pay somewhere between $300-400 for replacement. That experience will convince most people to stop pumping gas when the station’s pump clicks “off” for the first time.

I did notice a TSB about inspecting the tank for a vent valve that can allow fuel to leak in the event of a rollover. This TSB was really a recall,was this inspection done on your car? if not perhaps while it is getting done a look is also given to components that affect filling the tank.

There are many revisions made by the manufacture in regards to slow filling of the gas tank (so many that I am a bit set back).It seems to be a 50/50 mix of a design error with the fill pipe (or rollover equipment) versus damage to the charcol canister as to the cause of so many filling issues, there are alot of filling the tank issues out there.