Code result
P2277
O2 Sensor Signal Biased/Stuck Rich
High severity
What it means
O2 sensor at bank 2 sensor 3 reports a rich reading suspiciously stable for too long. Sensor 3 is typically downstream of the second catalyst on systems with three-stage aftertreatment; sensor coated with carbon or fuel residue is the typical cause.
Is it safe to drive?
No — stop driving
This code points to a problem that can cause damage or affect safety. Avoid driving and have the vehicle diagnosed promptly.
Most likely causes
Sensor coated
highOne of the most commonly reported causes for this code — check this first.
Related help
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