Getting ready to install a turbo timer into my 2001 A4 1.8T and have a question about which wire on the ECU side of the O2 Sensor connector is the signal wire and the ground wire. I have seen in the past where people have told others not to connect these two wires and merely just ground the ground wire to the chassis and be done. But I wouldn't mind having the O2 reading feature on my turbo timer. I have heard that the ground wire is 'brown' and that the signal wire is 'grey' from past posts. I just wanted to verify this before I start splicing into my ECU harness and mess my car up drastically. But if someone has a wiring diagram for the 2001 A4 (AWM) I will be more than happy to figure it out myself if it is provided to me. Thanks in advance for the help!

 

Anybody?