efficient.
Electronic fuel injection replaced older fuel-delivery systems.
Automatic transmissions gained additional gears and increasingly sophisticated computer controls.
Aerodynamics improved.
Tires were developed with lower rolling resistance.
All of these changes meant manufacturers could build fuel-saving behavior directly into the vehicle rather than asking the driver to select a separate economy position.
But the basic idea behind the old “E” never really disappeared.
Today, many vehicles offer an Eco mode.
Pressing an Eco button can change throttle sensitivity, transmission shift points, air-conditioning behavior, and other systems to reduce energy consumption.
