AutoCodes – Infiniti – P1421 Infiniti

P1421 Infiniti Code - Cold Start Control

Quick Answer

The Engine Control Module (ECM) controls ignition timing and engine idle speed when the engine is started with pre-warming up condition. Common causes include Lack of intake air volume (block air filter), Fuel injection system (Clogged fuel injector or bad fuel pump), Faulty Engine Control Module (ECM). 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: P1421 Infiniti indicates Cold Start Control.
Common causes: Common causes include Lack of intake air volume (block air filter), Fuel injection system (Clogged fuel injector or bad fuel pump), Faulty Engine Control Module (ECM).
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 21,644

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 Oct 07, 2022

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P1421 Infiniti Description

The Engine Control Module (ECM) controls ignition timing and engine idle speed when the engine is started with pre-warming up condition. This control promotes the activation of three-way catalyst by heating the catalyst and reduces emissions. The Diagnostic Trouble Code (DTC) will be set when the ECM does not control ignition timing and engine speed properly when the engine is started with prewarming up condition.

OBDII Code P1421 Infiniti - Cold Start Control - AutoCodes.com — P1421 Infiniti Code - Cold Start Control

What does this mean?

What are the Possible Causes of the DTC P1421 Infiniti?

Lack of intake air volume (block air filter)
Fuel injection system (Clogged fuel injector or bad fuel pump)
Faulty Engine Control Module (ECM)

How to Fix the DTC P1421 Infiniti?

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 is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P1421 Infiniti 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 P1421 Infiniti 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 P1421 Infiniti Code

1. What does OBDII code P1421 in an Infiniti refer to?

OBDII code P1421 in an Infiniti specifically relates to the Cold Start Control system.

2. What are the common symptoms of OBDII code P1421 in an Infiniti?

Common symptoms of OBDII code P1421 include rough idling, difficulty starting the engine, and decreased fuel efficiency.

3. What are the possible causes of OBDII code P1421 in an Infiniti?

The code P1421 in an Infiniti is commonly triggered by issues with the cold start control system, such as a faulty cold start valve or temperature sensor.

4. How can I diagnose the cause of OBDII code P1421 in my Infiniti?

To diagnose the cause of OBDII code P1421, it is recommended to perform a thorough inspection of the cold start control components, check for any loose connections, and conduct a comprehensive scan of the engine system.

5. Can I continue driving my Infiniti with OBDII code P1421?

While it may be possible to drive your Infiniti with the code P1421, it is recommended to address the issue promptly to prevent further damage to the engine and ensure optimal performance.

6. How can I repair OBDII code P1421 in my Infiniti?

Repairing OBDII code P1421 may involve replacing a faulty cold start valve, temperature sensor, or addressing any wiring or connection issues related to the cold start control system.

7. Are there any DIY tips for fixing OBDII code P1421 in an Infiniti?

DIY enthusiasts can attempt to address OBDII code P1421 by checking and cleaning the cold start valve, inspecting the temperature sensor, and ensuring all connections are secure.

8. Can a mechanic help me with OBDII code P1421 in my Infiniti?

Yes, consulting a qualified mechanic is recommended for accurate diagnosis and repair of OBDII code P1421 in your Infiniti to ensure the issue is resolved effectively.

9. Is resetting the OBDII system a solution for code P1421 in an Infiniti?

While resetting the OBDII system may temporarily clear the code, it is crucial to address the underlying issue causing code P1421 to prevent it from reoccurring.

10. What is the importance of fixing OBDII code P1421 promptly in an Infiniti?

Promptly fixing OBDII code P1421 in an Infiniti is essential to maintain optimal engine performance, fuel efficiency, and prevent potential long-term damage to the vehicle.