* Corrode fuel lines and other fuel system components: Ethanol is corrosive to certain materials commonly used in non-flex-fuel vehicles' fuel systems.
* Damage seals and gaskets: Ethanol can cause seals and gaskets to swell and fail, leading to leaks.
* Attract water: Ethanol absorbs moisture from the air, which can lead to rust and corrosion in the fuel system.
* Reduce fuel efficiency: While E85 has a higher energy content per gallon, it requires more fuel to produce the same amount of power, leading to decreased MPG.
* Run poorly or not at all: The engine may run rough, misfire, or even fail to start due to the different combustion characteristics of E85.
In short, never put E85 in a vehicle that isn't specifically designed and labeled as a "flex-fuel vehicle" (FFV). The potential for damage is significant and costly to repair.