How does a throttle position sensor work?

Throttle position sensors measure throttle blade angle and send this information to the engine ECU. Older designs use potentiometers (variable resistors) that output voltage proportional to position. Modern contactless sensors use Hall effect or inductive principles for better durability. Most systems have dual sensors for redundancy. The ECU uses throttle position along with other inputs to determine driver demand and control fuel injection and ignition timing.