Fuel is a dynamic liquid, and when you leave it to sit around, it can go bad. According to RoadandTrack.com, fuel starts to spoil after just 30 days, unless it’s stored in an entirely airtight container.
Unfortunately, a car’s fuel system isn’t airtight. As such, owners must preserve fuel in out-of-use vehicles. This is where fuel stabilizers come in. Designed to prevent oxidation in fuel, stabilizers extend the lifespan of fuel.