Definition
Flex fuel sensors inform the ECU so timing and fueling adjust automatically.
E85's higher octane supports more boost and timing on forced induction builds.
Automotive Wiki
Fuel
Flex Fuel
A fuel system and tune capable of running gasoline, E85, or blends by sensing ethanol content.
Related terms
- Fuel InjectorAn electronically controlled valve spraying atomized fuel into the intake port o…
- CarburetorA mechanical device mixing fuel and air using jets, venturis, and throttle plate…
- Direct InjectionFuel injection directly into the combustion chamber at high pressure.
- Port InjectionFuel sprayed into the intake port before the valve, mixing with incoming air.
- Octane RatingA measure of fuel resistance to knock under compression and heat.
- E85A blend of roughly 85% ethanol and 15% gasoline offering high knock resistance.
Category: Fuel · Updated August 31, 2026