How to Replace an Audi G28 Engine Speed Sensor Charles the Humble Technician shows you how to replace the G28 Engine Speed Sensor. This sensor is situated on the outside of the transmission just above the flywheel gear. It sends a message to the ECU via the grey wire T55/49 https://autolocksmiths59211.ampedpages.com/are-audi-a1-key-the-best-thing-there-ever-was-57106621