E100 is a liquid fuel composed entirely of hydrous or anhydrous ethanol without any gasoline blended in. It is used in dedicated alcohol-fueled vehicles, most notably in specific regional markets with vast biofuel infrastructure. Because it lacks the volatile components of gasoline, engines running on E100 often require special starting systems in cold weather.
Heard on the job
The new flex-fuel calibration struggles with cold starts when the tank is full of E100.
Also heard as
- neat ethanol
Do not mix it up with
- E85: E100 is pure ethanol, while E85 is a blend containing up to 85 percent ethanol and 15 percent gasoline to aid cold starting.