What causes P1149 on a Honda?

Aging primary oxygen sensor slow to switch on high-mileage Hondas Exhaust leaks ahead of the sensor diluting the exhaust sample Contaminated sensor from coolant, oil, or silicone sealants Frayed sensor wiring near the exhaust manifold heat shield

How do I fix P1149 on a Honda?

Monitor front O2S voltage switching and fuel trims on an HDS scan tool Smoke-check or listen for exhaust leaks at the manifold and flex pipe Inspect sensor wiring and connectors for heat damage Replace only with a Honda-spec or Denso/NGK equivalent primary sensor Clear codes and confirm fuel trims return toward zero on a road test

P1149 Primary HO2S Sensor 1 Circuit Range Performance Problem

Q: What does P1149 mean on a Honda?

P1149 — Primary HO2S Sensor 1 Circuit Range Performance Problem. Applies to Civic, Accord, CR-V, Odyssey.

Category: Powertrain - Fuel/Air Metering
Severity: Check Engine Light
Applies to: Civic, Accord, CR-V, Odyssey

What does P1149 mean on a Honda?

P1149 — Primary HO2S Sensor 1 Circuit Range Performance Problem. This Honda-enhanced code applies to Civic, Accord, CR-V, Odyssey.

Common causes of P1149

Aging primary oxygen sensor slow to switch on high-mileage Hondas
Exhaust leaks ahead of the sensor diluting the exhaust sample
Contaminated sensor from coolant, oil, or silicone sealants
Frayed sensor wiring near the exhaust manifold heat shield

How to fix P1149

Monitor front O2S voltage switching and fuel trims on an HDS scan tool
Smoke-check or listen for exhaust leaks at the manifold and flex pipe
Inspect sensor wiring and connectors for heat damage
Replace only with a Honda-spec or Denso/NGK equivalent primary sensor
Clear codes and confirm fuel trims return toward zero on a road test