100% Free

No Scanner Needed

Carly logo

P0401 - How To Repair: Meaning, Causes, Symptoms, Fixes

P0401 - OBD2 Trouble Code EGR Flow Insufficient Detected

P0401 Code Definition

Exhaust Gas Recirculation Flow Insufficient Detected

What Does the Engine Code P0401 Mean?

Character "P" in the first position of Diagnostic Trouble Code (DTC) represents the powertrain system (engine and transmission), "0" in the second position means that this is a generic OBD-II (OBD2) DTC. "4" in the third character position in a DTC indicates that the auxiliary emission controls system is experiencing a malfunction. The last two characters "01" is DTC number. OBD2 Diagnostic Trouble Code P0401 means that EGR Flow Insufficient Detected has been detected.

Carly's expert mechanics have identified the following related fault codes. With the information for these fault codes it is often possible to identify and better repair your faulty part/system:

Contents

    Carly Universal Scanner

    Carly Adapter
      iOS and Android enabled
      All car brands supported
      14-day money-back guarantee on the scanner
      Lifetime warranty with premium customer support
    Buy now

    What Is the Cause of P0401?

    There can be several damages/failures causing the underlying problem of the OBD2 DTC P0401. To find the root cause of P0401, unlock the “Smart Mechanic" feature in the Carly app.

    What Are the Symptoms of the Code P0401?

    Symptoms of a fault in the exhaust gas recirculation

      Severe power loss

      Illumination of the engine control lamp

      Strong soot formation during acceleration

      Irregular engine running

      Increased fuel consumption

      Jerking during acceleration

    Diagnostic background image

    How much does it cost to diagnose P0401?

    Visiting a car repair shop and letting them perform a diagnostics check can cost you $60-$100. For almost the same price you can get Carly. Its advanced features can cover what a professional automotive scanner that costs over $3,000 would, and more!

    Carly OBD2 Scanner

    How To Diagnose and Clear the Code P0401?

    Performing a diagnostics check with a diagnostic scanner helps you identify a particular problem area that is outside the normal range and shows where a fault might be occurring. This helps you to detect errors before they cause more damage to your vehicle. In comparison to generic OBD devices that only provide OBD-level engine-related data, Carly can run advanced manufacturer-level diagnostics, check all your ECUs in your car (like ABS, airbag, multimedia) and get deeper insights. You can find additional information about the trouble code and understand the severity of the problem. With the new Smart Mechanic feature, you get additional professional insights and tips from expert mechanics. You are able to check components and their mechanics, find detailed repair tips, and learn about potential future damage. After you have fixed the problem you can easily clear the fault codes with Carly, too. Also, the diagnostic results are safely stored inside the app or as convenient PDF reports you can share with your friends or a mechanic.

    Common Mistakes when diagnosing the P0401 code

    The most common mistake is to look and try to fix each individual OBD2 (OBD-II) code without having a holistic understanding and approach. Understanding the interrelationship of different systems is crucial to determining the root cause of the problem and finding the right solution. The new Carly Smart Mechanic feature provides a look at the whole system, not just one individual code. Enable Smart Mechanic in your Carly app and get a holistic solution-focused approach when diagnosing the code P0401.

    How Serious Is the Code P0401?

    For now, this issue is not serious. Carly recommends you to check this issue on a regular basis and check if it gets worse later on.

    How to fix the P0401 Code

    P0401 is a generic fault code but the repair steps may vary depending on the root cause and the make/model of your vehicle. Get the Smart Mechanic in your Carly app to learn more and receive guidance.

    Blurry background image
    Mobile and adapter showcase

    Estimated Cost of Repair for the P0401 Code

    The cost very much depends on the root cause of the issue. To find more information about causes, possible solutions, and potential repair costs, unlock “Smart Mechanic" content on the Carly app.

    Get Carly Now

    Learn more about the P0401 Code

    Exhaust gas recirculation function

    Exhaust gas recirculation (EGR) is a tested and well-tried method of reducing pollutants. A defined quantity of exhaust gas is extracted from the exhaust manifold and mixed back into the intake air. This reduces the proportion of oxygen in the fuel-air mixture and thus lowers the combustion temperature in the cylinders. Since harmful nitrogen oxides (NOx) are mainly produced at high temperatures and pressures, exhaust gas recirculation can reduce the amount of NOx emitted by up to 50 percent. In diesel engines, exhaust gas recirculation also reduces the formation of soot particles by around 10 percent.

    *Every car is unique. The Carly Features that your car supports depend on the model, build year, hardware, and software in the car. Plug the scanner in the OBD2 port, connect to the app, run your first diagnostics, and check which features are available for your car. Also, keep in mind that any information provided on this website is for informational purposes only and should be used at your own risk. Mycarly.com is not responsible for any errors or omissions, or for the results stemming from the use of this information.

    Code list background

    Top 10: The most common OBD2 trouble codes

    Our Partner

    dhl

    Our payment methods

    amex-logo
    apple-pay-logo
    google-pay-logo
    klarna-logo
    mastercard-logo
    paypal-logo
    visa-logo

    Car Brands
    carly-logo

    © 2024 Carly Solutions GmbH & Co. KG. All rights reserved