bank 1

  1. Chris

    The Official Jeep Wrangler TJ Oxygen (O2) Sensor Thread

    What are Bank 1, Bank 2, etc.? Since this question pops up from time-to-time, here's an easy to follow diagram that illustrates what they mean when your OBDII code scanner (or manual) tells you something like "O2 sensor, Bank 1, Sensor 2": What does upstream and downstream mean? Simple...