P0139 Lexus Code - Oxygen Sensor Circuit Slow Response Bank 1 Sensor 2
Quick Answer
The P0139 diagnostic trouble code (DTC) for Lexus vehicles specifically refers to the Oxygen Sensor Circuit Slow Response Bank 1 Sensor 2. Common causes include Faulty oxygen sensor, Wiring or connector issues, Exhaust leaks. Severity is Moderate - service should be scheduled soon. The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.
- What it means
- P0139 Lexus indicates Oxygen Sensor Circuit Slow Response Bank 1 Sensor 2.
- Common causes
- Common causes include Faulty oxygen sensor, Wiring or connector issues, Exhaust leaks.
- Severity
- Moderate - service should be scheduled soon.
- Can I drive?
- The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.
Code P0139 Lexus Description
The P0139 diagnostic trouble code (DTC) for Lexus vehicles specifically refers to the Oxygen Sensor Circuit Slow Response Bank 1 Sensor 2. This code indicates that there is a delayed response from the oxygen sensor located downstream (after the catalytic converter) on bank 1 of the engine. The oxygen sensor plays a crucial role in monitoring the air-to-fuel ratio in the exhaust gases, providing feedback to the engine control module (ECM) to adjust the fuel mixture for optimal combustion and emissions control.
Common Causes of P0139 Lexus
- Faulty oxygen sensor
- Wiring or connector issues
- Exhaust leaks
- ECM malfunction
- Contaminated or deteriorated sensor elements
Symptoms of P0139 Lexus
- Decreased fuel efficiency
- Engine misfires or hesitation
- Rough idling or stalling
- Illuminated check engine light
- Failed emissions test
How to Fix P0139 Lexus
- Begin by diagnosing the specific cause of the slow response, using a scan tool to read live data and pinpoint the issue.
- Inspect the oxygen sensor, wiring, and connectors for damage or corrosion, replacing any faulty components.
- Check for exhaust leaks and repair them as needed to prevent false readings from the oxygen sensor.
- Clear the DTC and test drive the vehicle to verify that the issue has been resolved.
- If the problem persists, further diagnostics may be required to identify any underlying ECM or sensor issues.
Cost to Fix P0139 Lexus
The cost of repairing a P0139 code can vary depending on the root cause of the issue. In general, replacing an oxygen sensor can range from $100 to $300, while addressing wiring or connector problems may add to the total cost. Labor rates at auto repair shops typically range from $80 to $150 per hour, so the total repair cost can add up depending on the time required to diagnose and fix the problem. It is advisable to consult with a trusted mechanic or dealership for an accurate estimate based on the specific details of the vehicle and the extent of the repair needed.
Tech Notes for P0139 Lexus
Need more information about the P0139 Lexus code?
Need more information on how to fix the P0139 Lexus code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the P0139 Lexus code diagnosed by a professional: Find a repair shop in your area
Frequently Asked Questions about P0139 Lexus Code
No Frequently Asked Questions about P0139 Lexus Code found.
Discuss the causes and fixes for P0139 Lexus OBDII Code
Code P0139 Lexus comments
No comments found for this page.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.