Monday Money-Saver: Enough is Enough

I'm talking gasoline again today, because, hey, that's what's on a lot of minds at the moment. Here is another simple tip for saving money at the pump:

When the pump clicks off, your tank is full. Yes, you can get a little more gas into the tank after that click - something we all call "topping it off," but that gas is basically going to be wasted. First, it may simply feed back into the gas pump's vapor recovery system. You see, that extra gas is going to evaporate very quickly, and the pumps are equipped with pollution-saving systems that are going to keep the gas from releasing into the air. When you top off your tank, you're sending a lot of that extra gas right back into the station. That's very generous of you, but I wouldn't expect to see gas prices drop because of your unknowing fuel philanthropy. Actually, it's not that simple. The recovery systems can become overloaded, causing the pump to malfunction for the next person and a lot of the excess gets released into the air anyway as a result. Not good.
What little gas you manage to actually get away with isn't going to do you much good, either.
That extra space in your tank is too allow for room for the vapor to expand. If it doesn't have that room , it has to expand somewhere, and in modern cars that is into the vapor collection system. This sounds like it's right where it's supposed to go, but too much all at once can cause the system to become fouled. This can cause expensive repair problems, and, again, a lot of that gas vapor is just going to go right into the air. None of it is actually being used to make your car move, but you paid for all of it and then some.
Topping off the tank is bad for your car, bad for the station pump, bad for the environment, and bad for your wallet. When the pump clicks off, it's telling you that you've got as much as your car can use.
Bonus tip: There's always going to be some evaporation during fill-up, but you can minimize the amount of gas that you pay for that doesn't actually go into your car by filling up before the sun is at its hottest. Plan your trips to the pump in the early morning or after dusk.