I too have been experiencing this same problem for about a year. I have removed several of the hoses and found those pesty pellets on the vent line (1/2" ID) . I have dumped them out and seem like my problem was solved. So I THOUGHT. Recently 1month ago the problem came back and yes pellets were found. I replaced the carbon canister and the problem was gone (again I thought). I had one tank fill (topped off) with neg problems. Next time (of course on a long trip) was the worse after the initial .5 gallons it lets me put in really sloooow at about 5 cents each time. Well after returning from the trip I cleaned out all the lines of pellets (not removed from the canister replacement) but still not better. I have blown out everthing and still no luck. I snaked the tank and managed to remove the tank shut off valve + spring by accident (NOT SURE how bad this will be) but did not help the problem. I have learned allot from previous post especially by JSINTON. I have some more test to conduct after reading all the previous post. I will advise. Any thoughts on this would be greatly appreciated.

I have also attempted to fill with a gas can and no better. The full tank valve is still removed

 

I covered the openings of the canister with fiberglass mesh and I don't get any charcoal anymore.

 

Ok first off I failed to mention this is a 2001 Sonata 2.4L auto

I tried an attempt this evening by disconnecting the larger 1/2 ID hose fro the tank to the carbon canister (at the canister) with no luck. I believe my next attempt will be to remove the hose at the vent itself. I am leaning toward the valve being in the stuck closed position. I dread removing the tank to inspect this valve. (the nuts look almost impossible to access with a deep well and universal due to the axle cross over) I will attempt to run some mousing wire into the vent to see if I can dislodge. I suspect the charcoal pellets made its way to the vent and have stuck it in the closed position. (if that is even possible). Well I will post after the second attempt (disconnect at the vent) is complete. I encourage any feed back. I also have no check engine lights on either. I have also renewed the canister .

Chris

 

OK made some headway. I disconnected two lines dirrectly at the fuel tank both lines go from vent to the 4 way valve. I filled the tank with no problems.

One of the lines is the 1/2 line which I have blown throu with lung pressure from the end of the "upside down trap" to the end with no obstruction.

1/4" has restriction blowing from tank side to outlet in fuel fill (by cap). There is a check valve there. In the past I may have put in the wrong dirrection.

Which way is the check valve suppose to go? Is it meant to allow air in (from cap to tank) and not let vapor out or am I backwards. I know there is an arrow on the check valve but as I stated it may have been installed wrong last time.

With everything back together i found that with the check valve not allowing vapor to escape to atmosphere then it shuts off immediately. If I reverse or simply remove I get much better flow (still not perfect) like I had when dirrectly removing lines dirrectly at tank.

I may need to remove the 1/2 line and see if it is disinegrated or collapsing inside. Any thoughts???

 

I have had trouble with my 2005 Hyundai Sonata since I got it new. I have had such a hard time getting the nozzle to lock down to fuel the vehicle that I had to leave, because people behind me were getting impatient. I took it to the dealership and they said they could not find any problem. It's really hard to have a gas powered vehicle if you can't put gas in it.

 

I HAVE FINALLY SOLVED THE PROBLEM AND APOLOGIZE FOR THE LONG DELAY .

This problem has ailed me for about 8 months and I did just about everything I could think of and things that were brought up in this forum. MY problem all stemmed from the carbon canister failure. I am probably the route cause because I have topped off my tank above "full" many times. Let this be a lesson to you all DO NOT try to squeeze every last drop into your fuel tank.

I first discovered the problem of failed canister when I too experienced the pump shutting off. I dissasembled the fuel vent/emmision lines and cleaned them out several times and replaced the canister. This help very minimum and my next step was to remove the vent located on the top of the fuel tank. I put this project off because it would require the removal of the fuel tank. I waited for warmer weather (which is a easy way to procastinate). Over the winter I came up with the idea to use a 4 1/2 hole saw I already owned and cut a hole dirrectly over the fuel tank vent.
Dont judge me I know its kinda redneck but hey its a 2001 hyundai and the hole was cut in the trunk next to a hole already cut in the trunk by the factory for fuel pump removal.


LONG STORY SHORT I REMOVED THE VENT VALVE AND THEN DISSASSEMBLE THE VENT VALVE AT THE TOP (THERE ARE 2 BENT OVER TABS THAT IF YOU STRAIGHTEN WILL ALLOW THE TOP ASSEMBLY TO COME APPART). I FOUND A LOT OF THE CARBON PELLETS INSIDE AND THEY WERE NOT ALLOWING THE BALL INSIDE THE VENT TO PUSH DOWN ON THE SHAFT THAT OPERATES THE OPENING OF THE VALVE IN NORMAL OPERATION).
ONCE I COMMITTED TO CUTTING INTO THE TRUNK VICE REMOVING THE VALVE THIS JOB TOOK ME ABOUT 30 MINUTES WHICH IS IS NOTHING COMPARE TO IF I DECIDED TO REMOVE THE TANK. I TOOK SOME SHEET METAL AND SEALANT PLUS SHEET METAL SCREWS AND SEALED THE HOLE TO PREVENT FUMES FROM ENTERING THE CAR.

NOTE THE ONLY WAY TO GET THIS VALVE OUT IS EITHER DROP THE TANK OR CUT INTO THE FLOOR OF THE TRUNK. NOT ONLY ARE THE SCREWS IMPOSSIBLE TO REMOVE WHILE THE TANK IS INSTALLED DUE TO LITTLE ROOM FOR YOUR TOOLS AND HANDS, THE VALVE IS APPROX 8 INCHES LONG AND WOULD NEVER BE ABLE TO COME OUT OF THE TANK BECAUSE AFTER YOU (IF YOU EVER COULD GET THE SCREWS OUT) THE VALVE WOULD ONLY SLIDE OUT ABOUT 1 INCH AND THEN HIT THE UNDERSIDE OF CAR BECAUSE THERE IS NO CLEARANCE.


THIS IS A LAST RESORT BUT FOR ME WAS ESSENTIAL. READ THROUGHT THE FORUM AND TAKE NOTE TO THE OTHER RECCOMENDATIONS OUT THERE THAT INVOLVE CHECKING AND CLEARING ALL THE TUBES/HOSES


GOOD LUCK ALL

 

Thanks for the information! I actually took my car in to Hyundai yesterday and they repaired that (or replaced it?). They did say that topping off the tank would cause the problem, which is good to know, but I bought my car new and it's done it since day one. That I don't understand. I rarely top my tank off, because the station that I go to says not to. Hopefully this is fixed now. Thanks so much for such a quick response. I only posted my message a couple of days ago.

 

U can fix this problem simply by removing the small hose going into the fuel canister as well. go ahead and leave the large hose connected but just simply disconnect the small hose.
yes this stops your vapor and maybe you will have 1mpg less traveling but when it's winter and you need to get gas it's worth it.

 

I actually have had this problem with my '05 Sonata since I bought it new. I seldom top my tank off and when I took it into the dealer the 1st time and complained, after putting up with it for over a yr, they said nothing was wrong with it. Now, my warranty is expiring (June 2010) so I took it into t different Hyundai dealership and they said it was the charcoal canister too. That may or may not be the problem, because it still gives me a headache. I actually have to put the nozzle in, crank it almost upside down and lean on it with my hip. Then I can lock it in and NOT MOVE. I love my car, but what good is it if you can't get gas in it? I have never experienced this with any other vehicle (mainly Toyota's & Nissan's). If it really was the canister, why is it still giving me trouble?