P2275
O2 Sensor Signal Biased/Stuck Rich Bank 1 Sensor 3
Fuel & air metering
Generic OBD-II
Medium
What it means
P2275 means the third oxygen sensor on bank 1 is reporting a signal stuck or biased toward rich. Usually the sensor itself or its wiring is at fault, but it can also flag a genuine rich-running condition. It mainly affects emissions and fuel economy rather than how the car drives.
Medium
Can I keep driving? Safe to keep driving — you may notice slightly rough running or higher fuel use, but it's mainly an emissions and monitoring fault.
Common symptoms
What you'll notice
- Check-engine light on
- Slightly rough or uneven idle
- Higher fuel consumption
- Occasional engine surge
Common causes
Most likely first
- Faulty Bank 1 Sensor 3 oxygen sensor (biased/stuck signal)Likely
- Wiring or connector fault at that O2 sensor — open, short, or corrosionCommon
- Genuine rich condition — leaking injector, high fuel pressureCommon
- Exhaust leak upstream of the sensor skewing the readingLess often
- Contaminated sensor (oil, coolant, or silicone)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame and live O2 data to confirm the sensor reads persistently rich.
- Inspect the Bank 1 Sensor 3 connector and wiring for damage or corrosion.
- Check for exhaust leaks near the sensor.
- Rule out an actual rich condition — fuel pressure, injectors, fuel trims.
- Replace the O2 sensor if wiring and fueling are good, then clear and re-test.
FAQ
Quick answers
Is it safe to drive with P2275?+
Yes. Drivability is barely affected, but it will fail an emissions test and can waste fuel, so repair it when convenient.
Can I just clear P2275?+
You can, but it comes back once the sensor reports rich again. Confirm whether the sensor or the fueling is at fault first.
Related codes
Often seen with P2275
Read & clear P2275 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX