How to Replace an Audi G28 Engine Speed Sensor In this video, Charles the Humble Mechanic shows how to replace the G28 engine speed sensor. This sensor is situated near the transmission's edge just above the flywheel gear. It sends a message to the ECU through the grey wire T55/49 https://car-locksmiths13564.bloggazza.com/29523095/question-how-much-do-you-know-about-audi-a1-key