AutoCodes – Nissan – P1146 2002 Nissan Altima Sedan

P1146 2002 Nissan Altima Sedan 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 2002 Nissan Altima Sedan 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 2,301

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 2002 Nissan Altima Sedan 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 2002 Nissan Altima Sedan - Heated Oxygen Sensor 2 Minimum Voltage Monitoring Bank 1 - AutoCodes.com — P1146 2002 Nissan Altima Sedan Code - Heated Oxygen Sensor 2 Minimum Voltage Monitoring Bank 1

What does this mean?

What are the Possible Causes of the DTC P1146 2002 Nissan Altima Sedan?

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 2002 Nissan Altima Sedan?

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 2002 Nissan Altima Sedan 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.

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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 2002 Nissan Altima Sedan Code

1. What are the common symptoms of OBDII code P1146 in a 2002 Nissan Altima Sedan?

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

2. What does the OBDII code P1146 on a 2002 Nissan Altima Sedan indicate?

- The code P1146 indicates an issue with Heated Oxygen Sensor 2 Minimum Voltage Monitoring Bank 1, specifically that the sensor is reporting a voltage below the minimum acceptable level.

3. What are the possible causes of OBDII code P1146 in a 2002 Nissan Altima Sedan?

- Possible causes include a faulty heated oxygen sensor, wiring issues, exhaust leaks, vacuum leaks, or a problem with the engine's air/fuel mixture.

4. How can I diagnose the cause of OBDII code P1146 in my 2002 Nissan Altima Sedan?

- A thorough diagnostic process involves checking the heated oxygen sensor, inspecting the wiring for damage, and performing a visual inspection of the exhaust system for leaks.

5. Can I continue driving my 2002 Nissan Altima Sedan with OBDII code P1146?

- It is not recommended to drive the vehicle with code P1146 unaddressed, as it can lead to poor engine performance and potential damage to other components.

6. How can I repair OBDII code P1146 in a 2002 Nissan Altima Sedan?

- Repair options may include replacing the heated oxygen sensor, repairing damaged wiring, fixing exhaust leaks, or addressing any issues related to the air/fuel mixture.

7. Is it safe to reset the check engine light after fixing OBDII code P1146 in my 2002 Nissan Altima Sedan?

- Yes, once the underlying issue causing code P1146 is resolved, it is safe to reset the check engine light using an OBDII scanner.

8. How long does it typically take to repair OBDII code P1146 in a 2002 Nissan Altima Sedan?

- The repair duration can vary based on the exact cause of the issue, but it may take anywhere from 30 minutes to a couple of hours to complete the necessary repairs.

9. Should I attempt to fix OBDII code P1146 in my 2002 Nissan Altima Sedan myself?

- If you have experience working on cars and access to the necessary tools, you may attempt to diagnose and repair code P1146. However, if you are unsure, it is best to consult a professional mechanic.

10. How much does it cost to fix OBDII code P1146 in a 2002 Nissan Altima Sedan?

- The cost of repairing code P1146 can vary depending on the cause of the issue, the parts needed, and whether you perform the repairs yourself or take the vehicle to a mechanic. Costs may range from $100 to $500 or more.