Advanced automotive electronics used to mean digital dashboard displays or electronic fuel injection. But carmakers are now moving toward a full electronic embrace of basic systems ranging from valve timing to steering. To provide the needed juice, they are adopting a new 42-volt electrical system, replacing the 14-volt standard that has reigned since 1955.

Ford Motor was first to make a public commitment with its January announcement that the Explorer sport utility vehicle will include a 42-volt system in 2004, initially enabling a new combined starter/alternator. The engine would shut off at every red light; a tap on the gas would fire the starter/alternator, moving the Explorer forward while rapidly restarting the engine. Ford predicts dramatic fuel economy gains.

Ford isn’t alone in trying to revamp the internal combustion engine with electromechanical components. Also hard at work are General Motors, DaimlerChrysler, BMW, Toyota and Renault. “Virtually all of the important manufacturers and suppliers have signed on to 42-volt,” says David Perreault, an electrical engineer at MIT’s Laboratory for Electromagnetic and Electronic Systems. The lab leads an industry consortium developing the technology, which will require new electrical systems and batteries.

Mercedes-Benz (now part of DaimlerChrysler) helped launch MIT’s 42-volt initiative in 1995 and is one of several companies developing one of its toughest applications: electromechanical engine valves. Such systems would replace today’s mechanical systems and provide superefficient combustion control, including shutdown of individual cylinders while others continue operating, saving fuel. A Mercedes spokesman offered no predictions, but Perreault expects electronic valves to reach drivers within a decade.

Other possibilities include electronic steering, which would eliminate the power-robbing steering pump and allow a computer to intervene if a driver’s jerky maneuver threatened a rollover. More immediately, luxury cars need extra juice to power new electronic trimmings like onboard navigators.