What is the shelf life of gasoline in a fuel tank?
2 Answers
Gasoline has a shelf life of approximately 3 months when stored in a sealed fuel tank at room temperature. Below is relevant information: Active ingredients: The active components of gasoline are its light fractions, which are highly volatile. Gasoline stored for too long will have reduced combustible components and increased concentration of heavy gum-like substances. Using such gasoline not only results in weak engine performance but also causes hazards like fuel injector clogging and rapid carbon buildup in the engine. Shelf life: The length of gasoline's shelf life is primarily determined by its oxidation stability, which refers to how easily the gasoline's quality changes during storage, distribution, and use. If the quality doesn't change easily, it indicates good stability and longer storage potential.
The shelf life of gasoline in the fuel tank largely depends on storage conditions and the type of gasoline. Based on decades of auto repair experience, fresh gasoline typically lasts about three months. However, if your car sits idle or experiences significant temperature fluctuations—like summer heat or winter cold—the shelf life can shorten to just one month. Ethanol-blended gasoline is even worse; its high volatility means it may degrade within one or two months due to moisture content promoting bacterial growth and fuel deterioration. Expired gasoline poses serious risks, potentially clogging or seizing engine fuel injectors—leading to hard starts at best or complete engine failure at worst. Adding fuel stabilizers can extend shelf life to six months, and regular short drives help circulate the fuel. If you notice darkened gasoline or unusual odors, address it immediately without delay.
