P0139 code means O2 Sensor Circuit Slow Response (Bank 1, Sensor 2).
The O2 sensors are used to measure the amount of oxygen in your exhaust system, which can then be used to determine how much fuel should be added to keep your engine running at its most efficient level.
If you get this code, either one or both of your O2 sensors have likely failed or become disconnected. In some cases, however, it could also mean something is wrong with your vehicle’s computer system (the ECU).
Common causes of the P0139 code, indicating a slow response from the downstream oxygen sensor, include:
Possible causes include a faulty oxygen sensor, wiring issues, vacuum leaks, or a deteriorating catalytic converter affecting sensor performance.
The downstream sensor measures the efficiency of the catalytic converter by analyzing oxygen levels in the exhaust after it has passed through the converter.
A slow response may indicate a decline in the catalytic converter’s efficiency, potentially leading to increased emissions and reduced fuel efficiency.
Yes, contaminants like oil or coolant on the sensor can hinder its response. Regular maintenance can help prevent such issues.
Solutions may involve replacing the oxygen sensor, fixing wiring issues, addressing vacuum leaks, or replacing a failing catalytic converter.
Costs vary based on the cause. Replacing an oxygen sensor may cost $100 to $300, while catalytic converter replacement can be more expensive.
Here’s a video that shows you how to fix P0139 engine code.
DISCLAIMER: Any information presented on RepairDost.com is for information purposes only. It is not intended as repair advice and we are not responsible for any actions you take on any vehicle. We do not take responsibility for inaccurate or incomplete results. All trademarks, trade names, service marks, product names and logos appearing on the site are the property of their respective owners.
AFFILIATE DISCLOSURE: Repairdost.com is a participant in the Amazon Services LLC Associates Program. As an Amazon Associate, we earn from qualifying purchases. This means that when you click on product links and make a purchase, we may earn a small commission at no extra cost to you. Thank you for your support!
©2024 RepairDost. All Rights Reserved.
Our website runs on eco-friendly hosting powered by renewable energy.