AutoCodes – Nissan – P0159 2009 Nissan Pathfinder

P0159 2009 Nissan Pathfinder Code - HO2S22 Slow Response

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 2, Rear Heated Oxygen Sensor Bank 2 harness is open or shorted, Rear Heated Oxygen Sensor Bank 2 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: P0159 2009 Nissan Pathfinder indicates HO2S22 Slow Response.
Common causes: Common causes include Faulty Rear Heated Oxygen Sensor Bank 2, Rear Heated Oxygen Sensor Bank 2 harness is open or shorted, Rear Heated Oxygen Sensor Bank 2 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.

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Code Popularity 1,869

How popular is this code, among other codes? Low

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 Mar 25, 2024

Description
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code P0159 2009 Nissan Pathfinder 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 P0159 2009 Nissan Pathfinder - HO2S22 Slow Response - AutoCodes.com — P0159 2009 Nissan Pathfinder Code - HO2S22 Slow Response

What does this mean?

What are the Possible Causes of the DTC P0159 2009 Nissan Pathfinder?

Faulty Rear Heated Oxygen Sensor Bank 2
Rear Heated Oxygen Sensor Bank 2 harness is open or shorted
Rear Heated Oxygen Sensor Bank 2 circuit poor electrical connection
Inappropriate fuel pressure
Faulty fuel injectors
Intake air leaks may be faulty
Exhaust gas leaks

How to Fix the DTC P0159 2009 Nissan Pathfinder?

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 O2 Sensor 2 usually takes care of the problem

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0159 2009 Nissan Pathfinder 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 P0159 2009 Nissan Pathfinder code?

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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 P0159 2009 Nissan Pathfinder Code

1. What does OBDII code P0159 mean for a 2009 Nissan Pathfinder?

Code P0159 indicates a slow response from the downstream oxygen sensor (HO2S22) in bank 2 of the exhaust system.

2. What are the common symptoms of OBDII code P0159 in a 2009 Nissan Pathfinder?

Common symptoms include poor fuel efficiency, rough idling, hesitation during acceleration, and potential issues with emissions.

3. What are the possible causes of OBDII code P0159 in a 2009 Nissan Pathfinder?

Possible causes include a faulty downstream oxygen sensor (HO2S22), wiring or connector issues, exhaust leaks, or a problem with the engine's air-fuel mixture.

4. How can I diagnose the cause of OBDII code P0159 in my 2009 Nissan Pathfinder?

Diagnosis typically involves inspecting the downstream oxygen sensor and its wiring, checking for exhaust leaks, and using a scan tool to monitor sensor data and response times.

5. How can I repair OBDII code P0159 in my 2009 Nissan Pathfinder?

Repair options may include replacing the downstream oxygen sensor (HO2S22), repairing or replacing damaged wiring or connectors, fixing any exhaust leaks, and addressing any issues with the air-fuel mixture.

6. Is it safe to continue driving my 2009 Nissan Pathfinder with OBDII code P0159?

It is generally not recommended to drive with a P0159 code, as it can lead to poor engine performance and potential damage if left unresolved.

7. Can a DIY enthusiast fix OBDII code P0159 in a 2009 Nissan Pathfinder?

Depending on their skill level and access to tools, a DIY enthusiast may be able to address the issue by replacing the downstream oxygen sensor or checking for wiring issues.

8. How much does it cost to repair OBDII code P0159 in a 2009 Nissan Pathfinder?

The cost of repairs can vary depending on the exact cause of the code and whether it can be fixed with a simple sensor replacement or if additional repairs are needed.

9. Will resetting the OBDII code P0159 in my 2009 Nissan Pathfinder make it go away permanently?

Resetting the code may temporarily clear the warning light, but if the underlying issue is not addressed, the code is likely to reappear after driving for a certain period.

10. How often should I have my 2009 Nissan Pathfinder's OBD system checked to prevent codes like P0159?

Regular maintenance checks, such as during scheduled services or if you notice any symptoms of engine trouble, can help catch potential issues before they trigger OBDII codes like P0159.