Engine Error
P2270
O2 Sensor Signal Biased/Stuck Lean (Bank 1 Sensor 2)
Severity
Low
Symptoms
Check engine light, failed emissions testing
Common Causes
- Exhaust leak near downstream O2 sensor
- Defective O2 sensor
- Water in sensor connector
- Failing catalytic converter
How to Fix
- 1 Repair exhaust pipe leak
- 2 Replace Bank 1 Sensor 2 O2 sensor
- 3 Clean and dry electrical connector
- 4 Test cat efficiency
Estimated Repair Cost
USD
$100
–
$400
O2 sensor replacement: $150 - $300; Exhaust repair: $100 - $200