Drive with caution — fix soon.
This code sets when the voltage from the bank 2 sensor 3 oxygen sensor stays too high, which can mean the sensor sees a constantly rich exhaust or that the signal wire is shorted to power or the sensor's reference is faulty. This downstream sensor supports emissions and catalytic converter monitoring. It's most often fixed by replacing the oxygen sensor, though wiring shorts, connector issues, or a genuine rich fuel condition should be checked first.
$150 – $400
Varies by vehicle and root cause.
Usually yes for short trips, since this rear sensor mainly affects emissions monitoring. If you smell raw fuel or the engine runs roughly, a rich condition may be involved and you should get it checked sooner. Otherwise a diagnosis within a week or two is fine.
Most repairs cost between $150 and $400, primarily the oxygen sensor plus about an hour of labor. If the real cause is a wiring short or a fuel system issue, the price can shift. Proper diagnosis avoids replacing a sensor that isn't actually bad.
It's generally a moderate concern. The vehicle remains drivable, but a persistent rich condition behind the high voltage can waste fuel and, over time, harm the catalytic converter. At the very least it will keep you from passing emissions, so plan to fix it.
It often does, because a high oxygen sensor voltage typically reflects a rich exhaust. However, the same high reading can come from a wire shorted to power or a contaminated sensor. A technician will review fuel trims and inspect the wiring before concluding whether it's the mixture or the sensor.