One fuel saving technology is the "start and stop" engine, that is, an engine that turns off at idle and restarts when power is needed. Mazda 's technology is called i-stop and will be available on the European Mazda 3 which is outfitted with a two litre four cylinder fuel injection engine. The system is novel in that it uses combustion energy for the engine restart which Mazda claims results in restarts twice as fast as conventional means. The system may not meet EPA regulations so don't expect to see the technology in the US.
[Source: CarandDriver.com]
