I have a 1981 K5 Blazer that doesn't like to take GAS..... I have dropped the tank and checked the lines and they are open, the fuel and vent hoses... At first, the length of the replacement hose was a problem as it had a bottom bend/loop that was restricting the flow. I shortened it and it got somewhat better, but, it still seems like the vent is plugged as the gas will not go in without turning on and off the fuel filler from the gas pump millions of times...... could there be a problem with the carbon canister?? Does it have one?? I haven't looked at that side yet, but, thought that it might be the problem.......... Anyone have this problem too??