Apparently from what I've read, the pressure builds up in the tank so it has a hard time idling. Might just need to find a way to vent the fuel fumes that build up pressure. I read somewhere that if you have less fuel it'll run, but if you have a full tank or whatever it'll have a hard time with idle. Idk though, I haven't done it because I'm stuck with the damn thing for emission testing... even though some sensor or whatever is fucked anyway