Powertrain
Definition only
Lights the check engine lamp
P22AF: O2 Sensor Reference Voltage Performance (Bank 1 Sensor 2)
Standardized SAE J2012 code · P22xx — Fuel & air metering and auxiliary emission controls
What does P22AF mean?
O2 sensor reference voltage on bank 1 sensor 2 is in range but plausibility check fails — drift or instability.
The code tells you which monitor failed, not which part is broken. Test before replacing parts.
Symptoms
- Check engine light on
- Increased fuel consumption
- Possible rough idle or hesitation
- Failed emissions test
Common causes
- High Reference voltage drift
Likelihood is a general estimate across vehicles; your make and model may differ.
Add your car to see reports of P22AF on the same make and model first.
P22AF in the community
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