o2 sensor

  1. V

    Technical 550i O2 sensor for single turbo

    This sensor recommendation is unverified, proceed at your own risk. Lately I've been hearing through the facebook grapevine of 550i O2 sensors being recommended for single turbo use. Then someone else told me they are the same as ADV, but I'm not sold on that claim. Realoem indicates they are...
  2. V

    Technical Single Turbo O2 sensor install and data

    Thought I'd make a thread to collect some data on O2 sensor options for the single turbo peeps. As everyone knows, 2-bank fueling logic forces ST kits to place the pre-cat O2s in the manifold between the head and turbine, exposing them to extremely harsh high temperature and positive pressure...
  3. Seaneezy

    2C7E/emissions codes lingering

    No idea what the hell is causing this anymore. The codes were involving both post-cat o2 sensors and pre-cat o2 sensors with lamba/mixture errors. I replaced both back o2 sensors and the front o2 sensor that was giving codes, they still appeared. At this point I assumed it had to do with my car...
  4. typedRew

    Secondary O2 sensors, tuned, still needed?

    On my last car, even though the 2nd cat codes were turned 'off' I needed the o2 sensor installed and plugged in to maintain proper fuel trims, not only did it need to be there but it could not be in a 'extended o2 tricker' housing. Had to be in the exhaust flow directly. I would get +12%-+18%...
  5. matreyia

    The Effect of Replacing O2 Sensors - Results

    Full FBO and MHD Wedge Tune. Was getting super duper shitty gas mileage - we talking 12mpg... Replaced all four o2 sensors and mileage shot back up like a rocket. Now 18-20 city and 23-24 highway. This is with down pipes. So if there is anyone who is wondering if changing o2 sensors after...