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p0420 fault exaust

  1. Faults P0420 - suspecting first O2 sensor

    Engines and Transmission (8G)
    Hello people First time thread posting, I hope I follow all the rules :) I got this awesome "Check system" message poping out, so I got OBD2 wifi ELM327, connected it to Torque Pro, and it read out P0420. (420! awesome) So next thing was to check behaviour of O2 sensor voltages, and I notice...