Engine-Codes.com
Engine-Codes – Infiniti – P1284 Infiniti

P1284 Infiniti Code - Air Fuel Ratio Sensor 1 Rich Shift Monitoring Bank 2

Quick Answer

The P1284 Infiniti diagnostic trouble code (DTC) indicates that there is a rich air-fuel mixture shift monitoring issue with the Air Fuel Ratio Sensor 1 in Bank 2 of the engine. Common causes include Faulty Air Fuel Ratio Sensor, Fuel injector issues, Vacuum leaks. 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
P1284 Infiniti indicates Air Fuel Ratio Sensor 1 Rich Shift Monitoring Bank 2.
Common causes
Common causes include Faulty Air Fuel Ratio Sensor, Fuel injector issues, Vacuum leaks.
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.
What is this?
Table of contents Created and updated by William Orellana on Sep 10, 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 P1284 Infiniti Description

The P1284 Infiniti diagnostic trouble code (DTC) indicates that there is a rich air-fuel mixture shift monitoring issue with the Air Fuel Ratio Sensor 1 in Bank 2 of the engine. This means that the sensor is detecting an abnormally high level of fuel in the air-fuel mixture, which can lead to poor fuel economy, decreased engine performance, and increased emissions. The Air Fuel Ratio Sensor is responsible for monitoring the oxygen content in the exhaust gases and sending this information to the engine control module (ECM) for proper fuel mixture adjustments. When the sensor detects a rich air-fuel mixture, it signals the ECM to adjust the fuel injection to lean out the mixture, but if this adjustment is not made correctly, it can result in a rich condition.

OBDII Code P1284 Infiniti - Air Fuel Ratio Sensor 1 Rich Shift Monitoring Bank 2
P1284 Infiniti Code - Air Fuel Ratio Sensor 1 Rich Shift Monitoring Bank 2

Common Causes of P1284 Infiniti

  1. Faulty Air Fuel Ratio Sensor
  2. Fuel injector issues
  3. Vacuum leaks
  4. Dirty or clogged air filter
  5. Faulty ECM

Symptoms of P1284 Infiniti

  1. Decreased fuel efficiency
  2. Rough idling or stalling
  3. Engine misfires
  4. Check Engine Light illuminated
  5. Strong fuel smell from the exhaust

How to Fix P1284 Infiniti

  1. Diagnose the issue using a scan tool to confirm the P1284 code and inspect the Air Fuel Ratio Sensor for any visible damage or contamination.
  2. Check the fuel injectors for proper operation and cleanliness. Clean or replace as needed.
  3. Inspect the vacuum lines for leaks or cracks and repair or replace as necessary.
  4. Replace the Air Fuel Ratio Sensor in Bank 2 if it is found to be faulty.
  5. Clear the DTC and test drive the vehicle to ensure the issue has been resolved.

Cost to Fix P1284 Infiniti

The typical repair costs for addressing a P1284 Infiniti code can range from $200 to $500, including parts and labor. However, the actual cost can vary depending on the specific vehicle make and model, the location of the repair shop, and the extent of the repairs needed. It is recommended to consult with a trusted mechanic or dealership for a more accurate estimate based on your individual circumstances.

What does this mean?

Tech Notes for P1284 Infiniti

If one or more sensors are replaced the Engine Control Module (ECM) Mixture Ratio Self-Learning clearing procedure must be performed.



There is a Factory Service Bulletin for the following Infiniti models:

2003-2012 Infiniti FX

2002 Infiniti G20

2003-2006 Infiniti G35 Sedan

2003-2007 Infiniti G35 Coupe

2006-2012 Infiniti G37 Sedan

2008-2012 Infiniti G37 Coupe

2002-2004 Infiniti I35

2004-2012 Infiniti M

2002-2006 Infiniti Q45

2002-2003 Infiniti QX4

2004-2012 Infiniti QX56

Infiniti Factory Service Bulletin OBDII Code P1284

When is the Code Detected?

The A/F signal computed by ECM from the A/F sensor 1 signal is shifted to the rich side for a specified period.

Need more information about the P1284 Infiniti code?

Need more information on how to fix the P1284 Infiniti code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1284 Infiniti code diagnosed by a professional: Find a repair shop in your area

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 P1284 Infiniti Code

No Frequently Asked Questions about P1284 Infiniti Code found.

Discuss the causes and fixes for P1284 Infiniti OBDII Code

Submit a New Comment

Code P1284 Infiniti comments

No comments found for this page.