Flex-fuel technology uses sensors and adaptive engine management to optimize combustion for any ratio of gasoline and ethanol, from pure gasoline (E27 in Brazil) to pure ethanol (E100). The driver chooses at the pump based on price — typically switching to ethanol when it costs less than 70% of gasoline.
Volkswagen launched the first commercial flex-fuel car in Brazil in March 2003 (Gol 1.6 Total Flex). Within five years, flex-fuel vehicles dominated new car sales. By 2025, over 90% of light vehicles sold in Brazil are flex-fuel.
The technology is now evolving: Stellantis launched a flex-fuel hybrid in 2024, and Toyota is testing a flex-fuel hydrogen engine in Brazil. The country is pursuing a 'technology-neutral' approach to vehicle decarbonization — not betting solely on battery-electric but allowing ethanol, hybrid, and hydrogen pathways to compete.