P2277

O2 Sensor Signal Biased/Stuck Rich Bank 2 Sensor 3

Severity

⚠️ Medium

Can you drive?

Yes, but get it checked soon

Approx. repair cost

$28–89 (est.)

Symptoms

Increased fuel consumption
Unstable engine idling
Reduced engine power
Check Engine Light Is On
Dips during acceleration

Causes

Oxygen sensor malfunction (Bank 2 Sensor 3)
Exhaust gas leak in front of the sensor
Malfunction of the catalytic converter
Problems with the fuel system (re-rich mixture)
Damaged or oxidized sensor wiring harness contacts

How to Fix

Check the status of the oxygen sensor Bank 2 Sensor 3
Inspect the exhaust system for leaks
Check fuel trim readings
Check the condition of the catalytic converter
Replace the faulty oxygen sensor if necessary

Related codes

P2279 P2278 P0172