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Fuel Tank

I have a 2002 Hyundai Accent.I am having trouble putting gas in the tank. This just started two weeks ago. When I squeeze the nozzle handle the auto shut off kicks in and I end up filling the tank by clicking the nozzle handle two dozen times. What is causing this problem?

There could be a number of issues here. If you are used to filling up the tank to get the last ounce in, I’m not surprised you have this problem.If the Evapotive Control System is plugged it will make itself known that way as well as causing the CEL light on the dash to come on.

Having said that, try different pumps; the local gas station where I used to tank up my Caprice caused the pump to keep shutting off. But other pumps worked OK. If all all pumps give you this problem, take the car to a good mechanic. The canister to catch the vapors might be the culprit, and be prepared for a hefty repair bill to correct it.

enter the words “slow fill” into the search box of this board…There are dozens of threads on this subject…

The problem lies in the evaporative emissions system.
Possible causes include:

A contaminated carbon canister. This results from forcing more gas into the tank after the pump clicks off for the first time. Do you, or does anyone else who drives the car, ever do this?

A kinked evaporative emissions hose.

A spider nest (really, this is not a joke) in one or more of the evaporative emissions hoses. Hyundais seem to be particularly prone to this problem.

A bad purge valve in the evap system

A problem with the “roll-over/check valve” device (I can’t recall the “official name” for this part) in the filler neck. This can frequently be cured by sticking a thin object (like a very thin hose or rod) down the filler neck.

Unless you can cure the problem by doing what is described in the last item, you will have to allow a mechanic to examine the car in order to try to diagnose the exact cause, but I am willing to bet a small sum that the problem results from one of the above situations.

You have been told a lot about what to do now, I would like to suggest that if you have a habit of topping off the tank when you fill up, rather than stopping when the pump first clicks off, you may have caused the problem. Likely your owner’s manual and a sticker somewhere on your car warns you about topping off the tank. BTW it is not cheaper to top off the tank, you just get a few additions miles before the next time you need to fill it.

[ Note: if you don’t have the sticker or the note in the owner’s manual, my advice may not apply.

The valve is called the “ROOF” valve. The EPA in 2000 required all passenger vehicles to have this valve. The acronym for ROOF is Roll Over/Over Fueling valve.

The EPA knew when people overfill the fuel tank, it damages the carbon canister in the EVAP system. So there’s float ball at the bottom of the fill neck to prevent overfilling of the gas tank. It rises to the bottom of the fill neck and shuts the pump off. So you can’t overfill the gas tank on a vehicle built after the year 2000. Hear that Joe?

This float ball also serves as a rollover valve. Because the EPA doesn’t want gasoline spilled into the environment. Below the float ball is a weight. So when the vehicle rolls over, instead of the float ball floating away from the fill neck, the weight forces the float ball against the fill tube, thereby preventing any gas from leaking from the fuel tank.


If you have local station that provides an attendant, just go there. This is not an uncommon problem and even if your car’s gas tank is the cause (likely), often an experienced gas jockey will be able to overcome the problem by positioning the nozzle correctly. Or else he or she will do the job the slow way.
If you must fill the tank yourself, pre-pay and ask if the pump can be set to deliver gasoline at the minimum flow. Otherwise, try to use the pump to deliver the lowest flow available, and expect to have the nozzle kick out every ten seconds or so.