Honda Error Code P0139: How to Fix It

Q: Can I drive my Honda with P0139 error code?

You can drive short distances, but the vehicle may have poor fuel economy, rough idle, and failed emissions tests. Replace the oxygen sensor promptly to prevent potential catalytic converter damage.

Q: How much does it cost to replace a Honda oxygen sensor?

DIY replacement costs $50-150 for the sensor plus tools. Professional repair typically ranges from $200-400 including labor, depending on sensor location and accessibility.

Q: What causes Honda P0139 oxygen sensor failure?

Common causes include normal wear after 60,000-100,000 miles, contamination from oil or coolant leaks, carbon buildup from poor fuel quality, or damaged wiring from heat and vibration.

Q: Will P0139 cause my Honda to fail emissions testing?

Yes, P0139 will likely cause emissions test failure since the downstream oxygen sensor monitors catalytic converter efficiency, which is a critical part of emissions control.

Q: How do I know which oxygen sensor is Bank 1 Sensor 2?

Bank 1 is the cylinder bank containing cylinder #1. Sensor 2 is downstream (after) the catalytic converter. On most Honda models, this sensor is located on the exhaust pipe behind the converter, closest to the muffler.

Abstract

Honda error code P0139 indicates that the downstream oxygen sensor (Bank 1, Sensor 2) is responding slowly to changes in exhaust gases. This sensor monitors the catalytic converter's efficiency, and when it fails, your engine may run poorly and emissions will increase.