Magneti Marelli Sistemas Automotivos Indústria & Comércio Ltda.


We are in the twilight of the fossil fuel era. In that light, we see extensive uses of flex fuels, to take advantage of renewable sources of fuel, e.g. ethanol or alcohol, mixed with gasoline, in fixed or variable ratios.

As fuel supplies, total costs, direct costs, and freedom from polluting effects, become increasingly problematic, the ability to utilize alternatives becomes increasingly desirable.

Magneti Marelli’s innovation, TETRAFUEL, reflects its ability to use any combination of pure gasoline, flex-fuel, pure ethanol – or CNG/GNV, compressed natural gas. This is a system comprised of two separate sets of injectors, and a single ECU capable of transparent switching dynamically between types automatically. A second innovation is the Sigma digital knock sensor, which inexpensively provides optimized ignition timing at each cylinder regardless of fuel type in use or the proportions.

A TETRAFUEL vehicle’s ECU is programmed to take advantage of the cost and environmental benefits of CNG whenever it is available, and switches to liquid fuel if the CNG runs out, or when extreme acceleration is required. TETRAFUEL’s ability to transition seamlessly between CNG, gasoline, ethanol, or flex-fuel, gives drivers anywhere great freedom in choosing the lowest cost, cleanest burning fuel options, and eliminates the risks of a specific fuel’s availability, because there isn’t total dependence on finding a source of CNG or ethanol.

Initial commercialization of TETRAFUEL is the Fiat Siena in Brazil, using the 1.4 L Fire TETRAFUEL engine.