Toyota’s flex-fuel prototype

Toyota recently unveiled a prototype of the Innova Hycross with a flex-fuel hybrid powertrain, its first car in India with this option, and one that the Japanese carmaker claims is the world’s first BS6 Stage II-compliant flex-fuel vehicle.

What is flex fuel technology?

• A flex fuel, or flexible fuel, vehicle has an internal combustion engine (ICE), but unlike a regular petrol or diesel vehicle, this can run on more than one type of fuel, or even a mixture of fuels.
• The most common versions use a blend of petrol and ethanol or methanol, but these engines are also equipped to run on 100 per cent petrol or ethanol as well.
• This is made possible by equipping the engine with a fuel mix sensor and an engine control module (ECM) programming that senses and automatically adjusts for any ratio of designated fuels.
• It was first developed in the early 1990sand used in the mass-produced 1994 Ford Taurus, according to Car Bibles. By 2017, there were approximately 21 million flex-fuel vehicles on the road.

Key Components of a Flex Fuel Car

• Battery: The battery provides electricity to start the engine and power vehicle electronics/accessories.
• Electronic control module (ECM): The ECM controls the fuel mixture, ignition timing, and emissions system; monitors the operation of the vehicle; safeguards the engine from abuse; and detects and troubleshoots problems.
• Exhaust system: The exhaust system channels the exhaust gases from the engine out through the tailpipe. A three-way catalyst is designed to reduce engine-out emissions within the exhaust system.
• Fuel filler: A nozzle from a fuel dispenser attaches to the receptacle on the vehicle to fill the tank.
• Fuel injection system: This system introduces fuel into the engine's combustion chambers for ignition.
• Fuel line: A metal tube or flexible hose (or a combination of these) transfers fuel from the tank to the engine's fuel injection system.
• Fuel pump: A pump that transfers fuel from the tank to the engine's fuel injection system via the fuel line.
• Fuel tank (ethanol/gasoline blend): Stores fuel on board the vehicle to power the engine.
• Internal combustion engine (spark-ignited): In this configuration, fuel is injected into either the intake manifold or the combustion chamber, where it is combined with air, and the air/fuel mixture is ignited by the spark from a spark plug.
• Transmission: The transmission transfers mechanical power from the engine and/or electric traction motor to drive the wheels.
  
  

 How flex fuel cars work?

• Flex fuel vehicles have one fuel system, and most components are the same as those found in a conventional petrol-only car.
• Some special ethanol-compatible components are required to adjust to the different chemical properties and energy content in ethanol or methanol, such as modifications to the fuel pump and fuel injection system.
• The ECM is also calibrated to accommodate the higher oxygen content of ethanol.