We now know that Mazda's trick engine start/stop function will be dubbed "i-stop," and its world debut will be this March at the Geneva Motor Show. It will first be fitted to the compay's Mazda3 compact equipped with a 2.0-liter DISI (direct-injected) four-cylinder.
2010 Mazda3Enlarge Photo
Mazda will also be displaying the next-gen Mazda3 MPS in Geneva (Mazdaspeed3 in the U.S.), the company's high-performance version of the Mazda3. Equipped with a 2.3-liter DISI with high-pressure turbocharging, this model will share the i-stop functionality of its stablemate and will now enjoy decreased consumption and lower emissions that will satisfy Euro Stage 5 requirements.
As we reported last fall, Mazda's stop/start system is unique in that the starter motor is not needed to get the engine firing again, making the engine re-start feature more rapid and transparent. Engine electronics position the pistons at shutdown such that injectors and sparkplugs are able to get the engine firing instantaneously.
Alas, you can't yet get your hands on i-stop in the U.S. for either version of the Mazda3 at the moment. Perhaps cheaper U.S. gasoline has Mazda Motors of North America less concerned with saddling U.S.-spec cars with the more expensive engine and technology. Still, in our full review of the 2010 Mazda3, we mentioned that fuel economy was a sore spot for the otherwise excellent compact. We hope Mazda fits i-stop to its U.S. offerings soon, especially before the inevitable rise of fuel prices.