Topping off your gas tank (aka gas topping) is not a good idea for mechanical, environmental, and financial reasons. Any gas you put in your car after the handle clicks doesn’t go into your gas system, so there is no benefit to topping it off.

Topping off your gas tank can lead to a hazardous leak due to excess pressure or even overwhelm your car’s evaporative system and break something. Something called a charcoal canister (aka carbon filter) is only designed for vapor. Topping off can lead to gasoline entering this canister, causing your car to run poorly and even damage your engine. A new charcoal canister will run you about $200.

Topping off can also be harmful to the environment if excess gasoline spills on the ground. Gasoline spills can contribute to ozone pollution (which can also be harmful to your health) and harm wildlife and pollute the water if it seeps into the ground.

I’ve been topping off my gas tank ever since I was a kid and don’t think I’ve ever had an issue, but now that I know it could cause problems and there is no benefit to doing it, I won’t be doing it going forward.

INTERESTING FACTS
  1. Nearly 20 gallons of gasoline can be refined from one barrel of oil, and one barrel of oil contains about 42 gallons of crude oil.
  2. Ethanol is added to gasoline because it results in the gasoline-burning cleaner and is less harmful to the environment.
  3. Drivers in the U.S. account for about 44% of the world’s gasoline consumption.
  4. The diesel engine was originally designed to run off of peanut oil. It got its name from its inventor, Rudolf Diesel.
INTERESTING VIDEO

INTERESTING REFERENCES
  1. AutomoBlog.net – TOPPING OFF: LEARN WHY YOU SHOULD NEVER TOP OFF YOUR GAS TANK
  2. FreeP.com (Detroit Free Press) – Why topping off your gas tank is a bad idea
  3. FuelExpress.com – 15 Fun Facts About Gasoline

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