AutoCodes – Nissan – P1146 2003 Nissan Sentra

P1146 2003 Nissan Sentra Code - Heated Oxygen Sensor 2 Minimum Voltage Monitoring Bank 1

Quick Answer

The Heated Oxygen Sensor 2 (HO2S) (Rear O2 Sensor), after three way catalyst (manifold), monitors the oxygen level in the exhaust gas on each bank. Common causes include Faulty heated oxygen (O2) sensor 2 (rear), Intake air leaks, Heated oxygen (O2) sensor 2 (rear) harness is open or shorted. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P1146 2003 Nissan Sentra indicates Heated Oxygen Sensor 2 Minimum Voltage Monitoring Bank 1.
Common causes: Common causes include Faulty heated oxygen (O2) sensor 2 (rear), Intake air leaks, Heated oxygen (O2) sensor 2 (rear) harness is open or shorted.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

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Code Popularity 3,621

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Intermediate (2 / 3)

What is this?

Table of contents Created and updated by William Orellana on May 01, 2019

Description
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code P1146 2003 Nissan Sentra Description

The Heated Oxygen Sensor 2 (HO2S) (Rear O2 Sensor), 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 P1146 2003 Nissan Sentra - Heated Oxygen Sensor 2 Minimum Voltage Monitoring Bank 1 - AutoCodes.com — P1146 2003 Nissan Sentra Code - Heated Oxygen Sensor 2 Minimum Voltage Monitoring Bank 1

What does this mean?

What are the Possible Causes of the DTC P1146 2003 Nissan Sentra?

Faulty heated oxygen (O2) sensor 2 (rear)
Intake air leaks
Heated oxygen (O2) sensor 2 (rear) harness is open or shorted
Heated oxygen (O2) sensor 2 (rear) circuit poor electrical connection
Inappropriate fuel pressure
Faulty fuel injectors

How to Fix the DTC P1146 2003 Nissan Sentra?

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 P1146 2003 Nissan Sentra 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 P1146 2003 Nissan Sentra 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 P1146 2003 Nissan Sentra Code

1. What are the common symptoms of OBDII code P1146 on a 2003 Nissan Sentra?

The common symptoms include poor fuel economy, rough idling, engine misfires, and the illumination of the check engine light.

2. What does OBDII code P1146 on a 2003 Nissan Sentra mean?

The code P1146 indicates an issue with the Heated Oxygen Sensor 2 Minimum Voltage Monitoring Bank 1 in the vehicle's exhaust system.

3. What are the possible causes of OBDII code P1146 on a 2003 Nissan Sentra?

Possible causes include a faulty oxygen sensor, wiring issues, exhaust leaks, vacuum leaks, or a problem with the engine's fuel system.

4. How can I diagnose the cause of OBDII code P1146 on my 2003 Nissan Sentra?

Diagnosing the issue may involve checking the oxygen sensor's wiring, inspecting for exhaust or vacuum leaks, and using a scan tool to monitor sensor data.

5. Can I continue driving my 2003 Nissan Sentra with OBDII code P1146?

It is not recommended to continue driving the vehicle with this code as it can lead to decreased fuel efficiency and potential damage to the engine over time.

6. How can I repair OBDII code P1146 on my 2003 Nissan Sentra?

Repairing the issue may involve replacing the Heated Oxygen Sensor 2, repairing any wiring faults, fixing exhaust leaks, or addressing any other underlying problems.

7. Should I reset the check engine light after fixing OBDII code P1146 on my 2003 Nissan Sentra?

Yes, it is recommended to reset the check engine light using an OBDII scanner after fixing the issue to clear the error code and ensure proper monitoring of the vehicle's systems.

8. Can a DIY enthusiast fix OBDII code P1146 on a 2003 Nissan Sentra?

Depending on the individual's skill level and access to tools, a DIY enthusiast may be able to fix the issue by following repair guides or seeking assistance from online forums.

9. How much does it cost to repair OBDII code P1146 on a 2003 Nissan Sentra at a mechanic?

The cost of repairing this code can vary depending on the exact cause of the issue, but it may range from $100 to $300 for parts and labor.

10. How often does OBDII code P1146 occur in 2003 Nissan Sentras?

The occurrence of this specific code can vary, but it is not an uncommon issue in older vehicles like the 2003 Nissan Sentra, especially as the oxygen sensor ages and becomes less efficient.