Electronic throttle control (ETC) is an automobile technology which severs the direct link between the accelerator pedal and the throttle. Most automobiles already use a throttle position sensor (TPS) to provide input to traction control, antilock brakes, fuel injection, and other systems, but use a long sheathed cable to directly connect the pedal with the throttle. An ETC-equipped vehicle has no such cable. Instead, an enhanced TPS feeds throttle-position data to a computer, which activates a solenoid to control the throttle.
The benefits of ETC are mostly unseen to drivers, so the feature is rarely even mentioned in consumer-oriented literature. The ETC computer can smooth out fuel delivery and acceleration, and can intervene for improved fuel economy or performance. Some drivers have complained about early ETC implementations "overruling" their decisions, however. In many cases, ETC reads not just the position of the pedal, but also its rate of change. This can lead to an odd non-linear relationship between pedal pressure and acceleration.
Similar technology has recently been applied to vehicle brakes, but this is much less common.
