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Problem fueling car

Hello,
I own a Hyndia Elantra 2000, 4spd. It was my son’s but he kindly passed it on to me when he purchased a new car. Lots of miles, over 150000. The alternator just died and was replaced. The current problem of about two months standing is that when trying to put gas into my car the fueling nozzle pops constantly as if my gas tank is already full. It takes me about 15 minutes to in put seven gallons. The other day I wondered if this is perhaps a dangerous problem and what might be causing it. Is there a cure? I accidentally drove through a small lake, thinking it was a small puddle about two months ago. Thankfully the car didn’t stop, but could there be water in the gas tank from my surprise 'swim"? The rest of the car is running OK (knock on wood)

Thanks to anyone who can help me with this problem.

The problem is most likely centered in the Evaporative Emissions System.

This is the apparatus that collects gas fumes from the tank, stores them temporarily in a carbon canister, and eventually routes them to the engine in order to be burned. However, when people have a habit of doing the “click-click-click” manuever with the gas filler nozzle in order to force more gas into the tank after the pump has clicked off, they wind up fouling the system by overfilling the tank, thus causing liquid gasoline to flow into the carbon canister. Once the carbon canister is saturated with gasoline, problems–such as yours–will take place.

Even if you have not forced more gas into the tank after the pump clicked off, it is possible that your son was in this habit. I guess that if I was about to cross the Atacama Desert, I might try to force as much gas into the tank as possible, but for the typical US driver with ready access to gas stations, this habit just makes no sense in the long run, as it can result in costly repairs. Replacing the carbon canister could cost a few hundred $$.

Also related to the Evap system is the possibility of (no, I am not kidding) spider nests inside the tubing of the evap system. For reasons that nobody can seem to figure out, Hyundais seem to be especially prone to the “spider syndrome”, which can also produce the symptoms that you described.

And, it is even possible that one of the evap system’s lines is kinked, or that the roll-over valve in the filler neck is in the wrong position. However, the one thing that you can rule out as a cause of this problem is driving through a large puddle. If there was water contaminating the gas, it would cause very rough engine operation and stalling, but would have no effect on the ability to put more gas into the tank.

I’m not sure about that VDC. The charcoal canisters on a lot of the modern cars are under the floorboards just foreward of the gas tank. If that lake somehow saturated the charcoal, it’d still choke the gas tank. And I don’t think it would get into the tank. The engine vacuum uponn startup when the purge valve opens would be insufficient to pull water out of the charcoal bed, so you might never know it was wet. Looking at my own system (which I should point out is NOT a 2000 Hyundai), it seems like an outside possibility.

http://tijil.org/Scion_Docs/05_tC_Shop_Manuals/Repair%20Info/Repair%20Manual/Fuel/Fuel%20Tank%20Assy/conponen.pdf