I've been getting a check engine light on and off for the past year. The code is P2096. I've been able to reset the code and add a bottle of Techron in the past, and the light will stay off for a few months. The Techron may just be a coincidence, but I've had the light come back on within a day or two if I don't add any. Sometimes the light will just go off on it's own anyway.

I borrowed a bluetooth OBDII scanner from a friend to monitor the O2 sensors. At idle, the front sensor seems to be pulsing normally between 0.1 - 0.7V. The rear sensor reads a constant voltage around 0.1V. From what I've read online, this seems like it's low. Would this indicate an exhaust leak, bad cat, faulty sensor, other?

Thanks!

 

MINI o2 sensors are notoriously junky. The near-zero flatline looks like a dead sensor to me. the sensor is supposed to read roughly 0.5v constant, indicating a steady exhaust stream and working catalytic converter. You will not likely be able to clear the light with your scan tool but there is a work-around on these forums to clear the lamp specifically for this code. Once you do that, swap the front and rear sensors- they are the same part number. If your check engine lamp comes back on the front, you can confirm the sensor is bad. I also dont recommend any aftermarket sensors, either. OEM are best.

 

i hate to bump an old thread but I have the same thing on a 2010 r56 base non turbo. After cat o2 is reading very low voltage compared to the before cat. I have a 30B2 "fuel injector cylinder 7 active" code as well as a 276A "catalytic converter -conversion" fault code coming up on my C110 diagnostic scan tool.

Ive read that I could have anything from a bad ignition coil to dirty injectors, but likely both are being caused by a bad catalytic converter.

Car has 95k on the odometer. Thanks for any responses.