P2379O2 Sensor Out of Range During Deceleration (Bank 2 Sensor 2)
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- P2379 covers the oxygen sensor behind the catalyst on bank 2 at the moment the injectors are shut off on a closed throttle: the exhaust is then close to fresh air, and a sensor whose reading stays outside the expected lean window is suspect. No manufacturer documents P2379 publicly. The nearest published logic is GM's bank 1 code P232F on the 2023 6.6L L5P, which compares the O2 value of the rear NOx sensor with the front one during overrun (window +3.01 to −3.18 %, Type B); that engine has no second bank. Ford checks the same sensor during fuel cut but reports under P013C, P014A or P2272/P2273. CARB asks at least for a rich-to-lean check of rear sensors in fuel shut-off. Code lists also give P239F this title. The car drives normally; the light points to sensor ageing or an exhaust leak.
- What you may notice
- Check engine light on
- No noticeable change in how the car drives
- Downstream O2 reading on bank 2 stays high during coasting in live data
- Likely causes
- LikelyBank 2 downstream sensor aged or contaminated, reacting too little to fuel cut
- PossibleExhaust leak near the bank 2 rear sensor diluting or distorting the sample
- PossibleChafed sensor lead or corroded connector on the bank 2 rear sensor
- RareLeaking injector on bank 2 keeping fuel in the exhaust during overrun
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Easy · Often possible to do yourself.Typical cost: €0 – €300
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.