AutoCodes – GMC – P1490 2021 GMC Sierra

P1490 2021 GMC Sierra Code - EVAP Purge Pump Voltage Sensor Performance

Quick Answer

Purge capacity is being reduced by technologies that improve fuel economy. Common causes include Faulty Evaporative Emission Purge Pump, Evaporative Emission Purge Pump harness is open or shorted, Evaporative Emission Purge Pump circuit poor electrical connection. 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: P1490 2021 GMC Sierra indicates EVAP Purge Pump Voltage Sensor Performance.
Common causes: Common causes include Faulty Evaporative Emission Purge Pump, Evaporative Emission Purge Pump harness is open or shorted, Evaporative Emission Purge Pump circuit poor electrical connection.
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 383

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Apr 18, 2023

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P1490 2021 GMC Sierra Description

Purge capacity is being reduced by technologies that improve fuel economy. The Evaporative Emission Purge Pump is used to purge stored vapors from the Evaporative Emission Canister and is required to increase the purge volumes to meet LEV 3 Evaporative Emission requirements. The Evaporative Emission Purge Pump has an integral pressure sensor for controlling purge vapors from the canister. The Engine Control Module (ECM) monitors the Evaporative Emission Purge Pump, and the Diagnostic Trouble Code (DTC) will be set when the EVAP Purge Pump Voltage and Ignition Voltage are not within 2.0 V of each other for greater than 1 s.

OBDII Code P1490 2021 GMC Sierra - EVAP Purge Pump Voltage Sensor Performance - AutoCodes.com — P1490 2021 GMC Sierra Code - EVAP Purge Pump Voltage Sensor Performance

What does this mean?

What are the Possible Causes of the DTC P1490 2021 GMC Sierra?

Faulty Evaporative Emission Purge Pump
Evaporative Emission Purge Pump harness is open or shorted
Evaporative Emission Purge Pump circuit poor electrical connection
Faulty Engine Control Module (ECM)

How to Fix the DTC P1490 2021 GMC Sierra?

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 P1490 2021 GMC Sierra 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 P1490 2021 GMC Sierra 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 P1490 2021 GMC Sierra Code

1. What are the common symptoms of OBDII code P1490 in a 2021 GMC Sierra?

- Common symptoms include rough idling, decreased fuel efficiency, and the illumination of the Check Engine Light.

2. What does the OBDII code P1490 on a 2021 GMC Sierra indicate?

- This code indicates a malfunction related to the EVAP purge pump voltage sensor performance.

3. What are the possible causes of OBDII code P1490 in a 2021 GMC Sierra?

- Possible causes include a faulty EVAP purge pump, damaged wiring or connectors, or a defective voltage sensor.

4. How can I diagnose the issue causing OBDII code P1490 in my 2021 GMC Sierra?

- Diagnosing the issue typically involves checking the EVAP system components, inspecting wiring for damage, and testing the voltage sensor.

5. Can I continue driving my 2021 GMC Sierra with OBDII code P1490?

- It is not recommended to drive with this code present, as it can lead to further damage and potentially affect the vehicle's performance.

6. How can I repair OBDII code P1490 in my 2021 GMC Sierra?

- Repairing this code may involve replacing the EVAP purge pump, repairing damaged wiring, or replacing the voltage sensor as needed.

7. Is it possible to clear OBDII code P1490 in a 2021 GMC Sierra by simply resetting the ECM?

- While resetting the ECM may temporarily clear the code, it is important to diagnose and address the underlying issue to prevent it from reoccurring.

8. Will OBDII code P1490 in a 2021 GMC Sierra cause emissions test failures?

- Yes, this code can cause your vehicle to fail emissions tests due to the malfunction in the EVAP system.

9. How can I prevent OBDII code P1490 from occurring in my 2021 GMC Sierra in the future?

- Regularly inspecting and maintaining the EVAP system, including the purge pump and associated components, can help prevent this code from reoccurring.

10. Are there any recalls or technical service bulletins related to OBDII code P1490 in a 2021 GMC Sierra?

- Check with your local GMC dealership or refer to online resources to see if there are any recalls or technical service bulletins related to this specific code in your vehicle.