Gas tank fueling problem

I have a 2003 Sonata Hyundai. For the last few months when I am trying to fill my gas tank the pump shuts off every 10 seconds or so. My tank is almost empty so it is not because the tank is full. My gas gauge is correct and not malfunctioning. It has been impossible to get a full tank of gas because the pump must be nursed along to put in small amounts of fuel, stop, and begin again. It is not the gas station as I have tried multiple gas stations and each time the pump shuts off fueling when only a small amount of gas has been put in.

On the “search” feature of this board, type “Slow Fill” and open dozens of threads on this subject. You are not alone…

The problem might be with the On-board Refueling Vapor Recovery system.

As the gas tank is filled, it is vented thru the carbon canister first to capture the fuel vapors before it’s allowed to vent to atmosphere. If there’s a restriction in this system the gas tank can’t vent properly as it’s being filled so the pump keeps kicking off.

Take it to a shop and ask that they inspect ORVR system for restrictions. There have even been cases of spiders building nests in this system causing this problem.

Tester

I might add to Tester’s comments that topping off the tank when you fill it can cause this problem. Many (all?) newer cars should never be topped off when filling up.

Thanks so much…I’m pointed in the right direction now.

I’m guilty of this practice. I didn’t know. Thanks!

You can’t overfill the gas tank on todays cars Joe. The anti-spill roll over valve serves two purposes. Not only does it prevent gas from spilling out of the gas tank in the event of a roll over, but it also prevents the over filling of the gas tank by floating up and blocking the fill tube, thereby preventing excess gas from being added to the gas tank and causing damage to the EVAP system.

Tester

Thanks Tester! I responded directly to your post but I never saw it come up.

Thanks Tester. Was there a give year when all (most all?) makes and models made the change? I would guess we are looking at only a few years that were subject to the problem of topping off?

The year 2000 all vehicles sold in the U.S. were mandated to have On-board Refueling Vapor Recovery systems and ROOF’s(Roll Over/Over Fill)valves.

Tester

Until you can get the ORVR system looked at, I’ve had success just pulling the nozzle of the pump out about halfway. I’ve had occasion to have this problem, and attribute it to the vapor recovery system of the pump, since it only happens once in a blue moon. That always seems to work for me.

good tip, thanks.

When you over-fill and float that check ball Tester mentioned, (which prevents further overfilling) the ball sometimes swells up and sticks in the closed position…SOMETIMES it can be freed by inserting a flexible switch down the filler neck far enough to dislodge the check ball…One of those fiberglass bicycle flag whips works good, so does a 3/8" plastic tube or hose…

ok, we’ll try this. thx,