New vehicles are changing every year, mostly because of developments in electronics. Vehicle systems that were mechanically controlled are now controlled by the vehicle’s computer. One such new system is electronic throttle control, known as drive-by-wire.

The drive-by-wire system eliminates the conventional mechanically operated system that had been used since the beginning of the cars. The standard mechanically operated accelerator pedal uses a cable attached from the pedal to the throttle body. When you pressed down on the pedal, the cable opens the throttle plate, allowing air to pass through into the engine. The engine RPM is directly proportional to the angle of the throttle plate. With drive-by-wire, the cable is replaced by an electronically controlled system using advanced electro-mechanical actuators. In place of a cable, an accelerator pedal position sensor is connected to the accelerator pedal. This sensor determines the position of the accelerator pedal and signals this information to the vehicle’s ECU, in turn, commands the throttle control motor to open or close the throttle valve.

The drive-by-wire system has its limitations; however, the main problem is that throttle response time is significantly slower. Throttle response, also known as vehicle’s responsiveness, is a measure of how fast an internal combustion engine can raise its power output from a low RPM to a higher more powerful RPM in response to a driver’s request for acceleration; pushing the pedal down. Throttle response is often jumbled with better power; however, throttle response is actually a measurement of the time taken for a change in power output.