Identical faults
The following faults are identical to P0172. For these, you can follow the information on this page:
P0175 – System Too Rich (Bank 2)
P0172 Code Definition
System Too Rich (Bank 1)
What Does the Engine Code P0172 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. "1" in the third character position in a DTC indicates that the fuel and air metering and auxiliary emission controls is experiencing a malfunction. The last two characters "72" is DTC number. OBD2 Diagnostic Trouble Code P0172 means that System Too Rich has been detected.
Repair How To's for related faults
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 Carly Adapter](https://cdn.mycarly.com/assets/adapter/adapter_mobile.png.webp)
What Is the Cause of P0172?
There can be several damages/failures causing the underlying problem of the OBD2 DTC P0172. To find the root cause of P0172, unlock the “Smart Mechanic" feature in the Carly app.
What Are the Symptoms of the Code P0172?
Symptoms of incorrect mixture formation
Power loss
Illumination of the engine control lamp/flashing of the engine control lamp
Rough engine running
Jerking during acceleration
![Diagnostic background image Diagnostic background image](https://cdn.mycarly.com/assets/banner/diagnosing_banner_mobile.jpg.webp)
How much does it cost to diagnose P0172?
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 ScannerHow To Diagnose and Clear the Code P0172?
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 P0172 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 P0172.
How Serious Is the Code P0172?
This issue is not critical yet. Make sure that it is current and fix it early before this leads to more severe issues.
How to fix the P0172 Code
P0172 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 Blurry background image](https://cdn.mycarly.com/assets/banner/blurry_bg_mobile.jpg.webp)
![Mobile and adapter showcase Mobile and adapter showcase](https://cdn.mycarly.com/assets/banner/app_adapter_showcase_mobile.png.webp)
Estimated Cost of Repair for the P0172 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 NowLearn more about the P0172 Code
Functionality of mixture preparation
In the internal combustion engine, the air-fuel mixture is compressed and ignited in a mixture ratio suitable for ignition and combustion. In the gasoline engine, ignition is triggered by an electric spark (spark plug). In diesel engines it is triggered by self-ignition (combustion pressure). The mixture formation begins when fuel is added to the intake air. The filling of the cylinders depends on the changing operating conditions (part load/full load) of the engine.The task of fuel metering is to adapt the fuel quantity to the respective air quantity. In the gasoline engine, there are two ways of doing this: The fuel quantity is allocated to the injection system or the air quantity is adjusted. An optimal ignition and combustion of the air-fuel mixture is only possible in a certain mixing ratio. In the case of gasoline, the ratio for complete combustion of the fuel (stoichiometric ratio) is on average 14:1. This means about 14 kg of air are required for complete combustion of 1 kg of fuel.
*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 Code list background](https://cdn.mycarly.com/assets/content-pages/gear_background_mobile.png.webp)