AutoCodes – Subaru – P0136 Subaru

P0136 Subaru Code - O2 Sensor Circuit Malfunction Bank 1 Sensor 2

Quick Answer

The heated oxygen sensor 2 (HO2S), after three way catalyst (manifold), monitors the oxygen level in the exhaust gas on each bank. Common causes include Faulty Rear Heated Oxygen Sensor Bank 1, Rear Heated Oxygen Sensor Bank 1 harness is open or shorted, Rear Heated Oxygen Sensor Bank 1 circuit poor electrical connection. 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: P0136 Subaru indicates O2 Sensor Circuit Malfunction Bank 1 Sensor 2.
Common causes: Common causes include Faulty Rear Heated Oxygen Sensor Bank 1, Rear Heated Oxygen Sensor Bank 1 harness is open or shorted, Rear Heated Oxygen Sensor Bank 1 circuit poor electrical connection.
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.

Save to My Repairs Step-by-Step Diagnostic Guide My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 44,160

How popular is this code, among other codes? Medium

Repair Importance Level

Moderate (Service soon) (2 / 3)

Repair Difficulty Level

Intermediate (2 / 3)

What is this?

Table of contents Created and updated by William Orellana on Jun 14, 2020

Description
Step-by-Step Diagnostic Guide
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code P0136 Subaru Description

The heated oxygen sensor 2 (HO2S), after three way catalyst (manifold), monitors the oxygen level in the exhaust gas on each bank. For optimum catalyst operation, the air fuel mixture (air-fuel ratio) must be maintained near the ideal stoichiometric ratio. The HO2S output voltage changes suddenly in the vicinity of the stoichiometric ratio. The Engine Control Module (ECM) adjusts the fuel injection time so that the air-fuel ratio is nearly stoichiometric. The HO2S generates a voltage between 0.1 and 0.9 V in response to oxygen in the exhaust gas. If the oxygen in the exhaust gas increases, the air-fuel ratio becomes Lean. The ECM interprets Lean when the HO2S voltage is below 0.45 V. If the oxygen in the exhaust gas decreases, the air-fuel ratio becomes Rich. The ECM interprets Rich when the HO2S voltage is above 0.45 V.

OBDII Code P0136 Subaru - O2 Sensor Circuit Malfunction Bank 1 Sensor 2 - AutoCodes.com — P0136 Subaru Code - O2 Sensor Circuit Malfunction Bank 1 Sensor 2

What does this mean?

What are the Possible Causes of the DTC P0136 Subaru?

Faulty Rear Heated Oxygen Sensor Bank 1
Rear Heated Oxygen Sensor Bank 1 harness is open or shorted
Rear Heated Oxygen Sensor Bank 1 circuit poor electrical connection
Inappropriate fuel pressure
Faulty fuel injectors
Intake air leaks may be faulty
Exhaust gas leaks

How to Fix the DTC P0136 Subaru?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What does this mean?

Code Tech Notes

Replacing the Rear Heated Oxygen Sensor Bank 1 usually takes care of the problem.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0136 Subaru code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the P0136 Subaru code?

Need more information on how to fix the P0136 Subaru code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0136 Subaru code diagnosed by a professional: Find a repair shop in your area

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P0136 Subaru Code

1. What are common symptoms of OBDII code P0136 in a Subaru?

- Common symptoms include poor fuel economy, rough idling, engine misfires, and the illumination of the Check Engine Light.

2. What does the OBDII code P0136 for a Subaru indicate?

- OBDII code P0136 indicates an O2 Sensor Circuit Malfunction in Bank 1 Sensor 2, typically pointing to issues with the downstream oxygen sensor.

3. What are possible causes of the P0136 OBDII code in a Subaru?

- Possible causes include a faulty oxygen sensor, damaged wiring or connectors, exhaust leaks, or issues with the engine's computer system.

4. How can I diagnose the O2 sensor circuit malfunction in my Subaru related to code P0136?

- Diagnose by inspecting the oxygen sensor wiring, checking for exhaust leaks, testing the sensor's voltage output, and verifying the sensor's response to changes in air/fuel ratio.

5. Can I drive my Subaru with OBDII code P0136?

- While the car may still be drivable with this code, it is not recommended as it can lead to further damage, reduced fuel efficiency, and potential engine performance issues.

6. How do I repair the O2 sensor circuit malfunction in my Subaru triggered by code P0136?

- Repair involves replacing the Bank 1 Sensor 2 oxygen sensor, ensuring proper wiring connections, fixing any exhaust leaks, and clearing the error code.

7. Will resetting the Check Engine Light resolve the P0136 OBDII code in my Subaru?

- Resetting the Check Engine Light may temporarily clear the code, but it will likely reappear if the underlying issue causing the O2 sensor circuit malfunction is not addressed.

8. Are there any maintenance tips to prevent the recurrence of code P0136 in my Subaru?

- Regularly inspect and maintain the oxygen sensors, address any exhaust system leaks promptly, and follow the manufacturer's recommended service schedule to prevent O2 sensor circuit malfunctions.

9. How much does it cost to repair the O2 sensor circuit malfunction related to code P0136 in a Subaru?

- The cost of repair can vary depending on the cause of the issue, but it typically ranges from $200 to $500 for parts and labor.

10. Can a DIY enthusiast replace the Bank 1 Sensor 2 oxygen sensor in a Subaru to resolve code P0136?

- While it is possible for a skilled DIY enthusiast to replace the oxygen sensor, it is recommended to consult a professional mechanic to ensure proper installation and diagnosis of the issue.