For example, the optimized engine Auto Start Stop feature now turns the engine off earlier while coasting to a stop.

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The 2013 Kia Rio, for instance, joins the BMW 3-series and Porsche Cayenne in offering a start-stop engine.

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The Delphi connectivity system's key fob service operates over the Verizon Wireless network or via Bluetooth to remotely lock or unlock doors, open the trunk, start or stop the engine and operate a panic horn on select vehicles.

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Even if that engine has to stop and start at each new town.

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Maximum fuel economy is achieved in ECO mode, with the stop-start on and engine response and output dialed way back.

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Meanwhile, the feds' fuel-economy administrators are currently operating at a dead run trying to keep up with a host of new, highly digitized fuel-saving technologies, such as "Eco" throttle mapping and stop-start (the engine cuts out as the vehicle coasts or stops), which were practically invented to hack the EPA testing cycle.

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At what point do you stop, attempting to start the engine?

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Work will continue to give Ariane 5 a major upgrade, to provide it with a more powerful upper-stage engine that will also have a stop-start capability.

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