 Another feature of older flex-fuel cars is a small separate gasoline storage tank that was used for starting the car on cold days, when the ethanol mixture made ignition more difficult.Modern Brazilian flex-fuel technology enables FFVs to run an any blend between E20-E25 gasohol and E100 ethanol fuel, using a lambda probe to measure the quality of combustion, which informs the engine control unit as to the exact composition of the gasoline-alcohol mixture.This technology, developed by the Brazilian subsidiary of Bosch in 1994, and further improved and commercially implemented in 2003 by the Italian subsidiary of Magneti Marelli, is known as "Software Fuel Sensor".