P1157 Air/Fuel Sensor Bank 1 Circuit Malfunction
What does P1157 mean on a Honda?
P1157 — Air/Fuel Sensor Bank 1 Circuit Malfunction. This Honda-enhanced code applies to Civic, Accord, CR-V with wideband A/F sensors.
Common causes of P1157
- Aging bank 1 air/fuel sensor responding slowly
- Contaminated sensor from coolant or silicone
- Exhaust leak diluting the bank 1 sample
- Corroded A/F sensor connector
- Bank 1 fuel control fault skewing readings
How to fix P1157
- Compare bank 1 sensor waveform to a known-good pattern
- Smoke test the exhaust manifold and downpipe
- Check for coolant loss or recent silicone use
- Fix fuel trim faults first
- Replace the bank 1 sensor after excluding leaks