How to Replace an Audi G28 Engine Speed Sensor Charles the Humble Technician teaches how to replace the G28 Engine Speed Sensor. This sensor is located at the edge of transmission, above the flywheel gear. It transmits a signal the ECU via a grey wire (T55/49), then to the tachometer https://carlocksmiths21334.answerblogs.com/29994913/looking-for-inspiration-check-out-audi-a1-key