The Surprising Short Shelf Life of Gasoline.

Gasoline can expire in as little as four weeks if left dormant in a vehicle's tank. Fuel stabilizers can extend the shelf life from one to three years in optimal conditions. Ethanol in gasoline can bond with water and corrode the engine. Gasoline is made up of only the lightest hydrocarbons out of crude oil, and leaving it too long can result in some of those molecules evaporating away. To maximize gasoline's shelf life, it should be stored in a full container in a constant temperature and low humidity environment.