<img src="/forums/images/graemlins/kewl.gif" alt="" />I have an air/fuel gauge which shows that the 02 sensor is sending a good reading to the ecu.It has indicator lights that should constantly flash up and down the scale of the gauge to show the ecu is constantly looking for the right fuel mixture.Right now the 02 works when the cold start high idle is running.But it seems to stop working after warmup.I just get a constant set of lites towards the lean side of the gauge with no flashing.I'm not sure if this is open or closed loop on the ecu.Maybe someone a little more knowledgable will chime in about that. <img src="/forums/images/graemlins/cheers.gif" alt="" />