How to Replace an Audi G28 Engine Speed Sensor In this video Charles the humble mechanic demonstrates how to replace the G28 engine speed sensor. This sensor is situated at the edge of transmission, above the flywheel gear. It sends a message to the ECU through a grey wire T55/49, https://carlocksmiths68698.bloggazzo.com/29563436/5-clarifications-on-audi-a1-key