I have failed the emisson test in my State due to a pressure test from fill tube to charcoal cannister. I have replace every gasket and hose from the tank to the cannister except for the grommet and the valve on top of each of the fuel tanks but I have no Idea where to find them or what they are called. I have a 1994 supercab with a 350 engine and dual tanks. I've checked under vent valves, check valves but are unable to find. Can anyone help?

 

Do you have the ratchet tight type gas caps & both have seals that aren"t cracked or compressed?

 

What state are you in? I'm in AZ. And failed that part of the test also. It passed the gas cap test. My truck is a 95 f150. Basically same truck you have. I'm not sure if the idiots were looking at the wrong line since I couldn't see. I checked the line going to the canister and they were good.

How do you pressurize the tank so you can check for leaks? I had the line that goes to the canister disconnected and when I spun the fuel cap off there was pressure coming out. It makes me think the line is clogged or there's a one way valve that has to have a certain amount of psi before it opens.

 

Well I found my problems. Someone blocked off the lines to the main canister line. Why would someone do this? The vapors aren't hurting the performance of the truck. Some people are just dumbasses.