Engine-CodesToyota – P0159 Toyota

P0159 Toyota Code - HO2S22 Circuit Slow Response

Quick Answer

The P0159 code for Toyota vehicles specifically refers to an issue with the HO2S22 (Heated Oxygen Sensor 2 Sensor 2) circuit having a slow response. Common causes include Faulty HO2S22 sensor, Damaged wiring or connectors related to the sensor, Vacuum leak in the intake system. 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 Toyota indicates HO2S22 Circuit Slow Response.
Common causes
Common causes include Faulty HO2S22 sensor, Damaged wiring or connectors related to the sensor, Vacuum leak in the intake system.
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.
Table of contents Created and updated by William Orellana on Sep 09, 2024
💬 Need more help? Ask Auto Expert for instant answers — it's free!
AutoCodes App

Fix Your Car Smarter

Try the New AutoCodes App!

Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.

AutoCodes App on Google Play

Code P0159 Toyota Description

The P0159 code for Toyota vehicles specifically refers to an issue with the HO2S22 (Heated Oxygen Sensor 2 Sensor 2) circuit having a slow response. The HO2S22 sensor is responsible for monitoring the oxygen levels in the exhaust gases after they have passed through the catalytic converter. This data is crucial for the engine control module (ECM) to adjust the air-fuel mixture for optimal combustion and emissions control.

OBDII Code P0159 Toyota - HO2S22 Circuit Slow Response
P0159 Toyota Code - HO2S22 Circuit Slow Response

Common Causes of P0159 Toyota

  1. Faulty HO2S22 sensor
  2. Damaged wiring or connectors related to the sensor
  3. Vacuum leak in the intake system
  4. Exhaust leaks near the sensor
  5. ECM malfunction

Symptoms of P0159 Toyota

  1. Decreased fuel efficiency
  2. Rough idling
  3. Hesitation during acceleration
  4. Check Engine Light illuminated
  5. Failed emissions test

How to Fix P0159 Toyota

  1. Begin by visually inspecting the wiring and connectors related to the HO2S22 sensor for any signs of damage or wear.
  2. Test the HO2S22 sensor using a multimeter to check for proper voltage output and response time.
  3. Check for any vacuum leaks in the intake system and repair as necessary.
  4. Inspect the exhaust system for leaks near the sensor and address any issues found.
  5. If the issue persists, consider replacing the HO2S22 sensor or seeking professional help for further diagnosis and repair.

Cost to Fix P0159 Toyota

The cost of repairing a P0159 code can vary depending on the cause of the issue and the specific vehicle. On average, replacing an oxygen sensor can cost between $200 and $300, including parts and labor. However, if the issue is related to wiring or other components, the cost may increase. It is recommended to consult with a trusted mechanic or dealership for a more accurate estimate based on the specific circumstances of your vehicle.

Tech Notes for P0159 Toyota

Replacing the O2 Sensor 2 usually takes care of the problem

When is the Code Detected?

The P0159 code is set when the Engine Control Module (ECM) detects that the rear O2 sensor takes more time to respond between rich and lean than the specified time.

Need more information about the P0159 Toyota code?

Need more information on how to fix the P0159 Toyota code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0159 Toyota code diagnosed by a professional: Find a repair shop in your area

Information for Specific Toyota Models

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 Toyota Code

No Frequently Asked Questions about P0159 Toyota Code found.

Discuss the causes and fixes for P0159 Toyota OBDII Code

Code P0159 Toyota comments

No comments found for this page.