What causes P1157 on a Honda?

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 do I fix P1157 on a Honda?

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

P1157 Air/fuel ratio sensor (sensor 1) range/performance problem

Q: What does P1157 mean on a Honda?

P1157. Air/fuel ratio sensor (sensor 1) range/performance problem. Applies to Civic, Accord, CR-V with wideband A/F sensors.

Category: Powertrain - Fuel/Air Metering
Severity: Check Engine Light
Applies to: Civic, Accord, CR-V with wideband A/F sensors

What does P1157 mean on a Honda?

P1157. Air/fuel ratio sensor (sensor 1) range/performance problem. 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

Sources and review

Last updated 2026-09-24.