Originally Posted by NewoIkkin
what does that mean?
Like when you fill up your tank and the nozzle clicks off, some people continue to try pumping gas after that. That's topping off the tank.
Anyway, the reason why it's not good for our cars (or most cars, in general) is that the extra gas may get into the vapor recovery system and clog it up. I think this has happened to other people and it has caused their cars not to start.