AutoCodes – Nissan – P1146 2004 Nissan Altima Sedan

P1146 2004 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 2004 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 2,134

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 2004 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 2004 Nissan Altima Sedan - Heated Oxygen Sensor 2 Minimum Voltage Monitoring Bank 1 - AutoCodes.com — P1146 2004 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 2004 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 2004 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 2004 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 2004 Nissan Altima Sedan Code

1. What does OBDII code P1146 mean for a 2004 Nissan Altima Sedan?

The code P1146 indicates a problem with the Heated Oxygen Sensor 2 Minimum Voltage Monitoring Bank 1 in a 2004 Nissan Altima Sedan.

2. What are the common symptoms of OBDII code P1146 in a 2004 Nissan Altima Sedan?

Common symptoms of code P1146 may include poor fuel economy, rough idling, hesitation during acceleration, and potentially an illuminated check engine light.

3. What are the possible causes of OBDII code P1146 in a 2004 Nissan Altima Sedan?

Potential causes of code P1146 include a faulty heated oxygen sensor, wiring issues, exhaust leaks, or problems with the engine's air-fuel mixture.

4. How can I diagnose the issue related to OBDII code P1146 in my 2004 Nissan Altima Sedan?

Diagnosing code P1146 typically involves using an OBDII scanner to read the code, inspecting the oxygen sensor and its wiring, checking for exhaust leaks, and testing the air-fuel mixture.

5. Can I continue driving my 2004 Nissan Altima Sedan with OBDII code P1146?

It is not recommended to continue driving with an unresolved P1146 code, as it can lead to decreased fuel efficiency and potential damage to the vehicle's catalytic converter.

6. How can I repair OBDII code P1146 in my 2004 Nissan Altima Sedan?

Repairing code P1146 may involve replacing the heated oxygen sensor, repairing any wiring issues, fixing exhaust leaks, or addressing problems with the air-fuel mixture.

7. Is it possible to reset OBDII code P1146 in a 2004 Nissan Altima Sedan without fixing the underlying issue?

While you can clear the code using an OBDII scanner, the check engine light is likely to come back on if the root cause of the problem is not addressed.

8. How much does it typically cost to repair OBDII code P1146 in a 2004 Nissan Altima Sedan?

The cost of repairing code P1146 can vary depending on the specific issue, but it may range from $100 to $300 for parts and labor.

9. Can a DIY enthusiast fix OBDII code P1146 in a 2004 Nissan Altima Sedan?

Depending on the root cause of the issue, some DIY enthusiasts may be able to address code P1146 themselves by replacing the oxygen sensor or fixing wiring problems.

10. How often does OBDII code P1146 occur in a 2004 Nissan Altima Sedan?

Code P1146 related to the Heated Oxygen Sensor 2 Minimum Voltage Monitoring Bank 1 is a relatively common issue in 2004 Nissan Altima Sedans and may occur due to various factors affecting the oxygen sensor's performance.