I've seen two other threads about hard to fill gas tanks, and I have the same problem. About 1/2 second after squeezing the gas pump handle, it shuts off. I did overfill my gas tank one day, and I think that is when it started. I never knew why it was bad to overfill, but after reading all about the evaporative system, I now know. I promise I won't do it again. Anyhow, I totally removed my charcoal canister (all 3 hoses removed), and I still cannot fill my gas tank! I thought it was a bad canister, but I guess not since my problem still occurred after removing it. Now I think it is a fuel shutoff valve or a 2 way valve. I can't find an accurate diagram at the hyundai website though. I think I will replace the fuel shutoff valve, the 2 way valve, and the canister. I was wondering if someone could help me with removing the gas tank, and where the shutoff valve and 2 way valve are located?