FSI (fuel-stratified injection) is a technology that increases the torque and power of spark-ignition engines, making them as much as 15 per cent more economical and reducing exhaust emissions.

Use less fuel, get more power. The FSI system uses two charge-air supply modes: stratified charge at partial load and homogeneous operation at full load. In the stratified charge mode, a combustible fuel-air mixture is only produced in a defined zone around the spark plug. The engine management electronics monitor engine load and adjust injection timing, pressure, quantity parameters and air flow inside the cylinder via the air intake channel. At full load, FSI increases compression as well as engine efficiency and performance.