What Is Chevy Code P0171 & How To Fix Too Lean Condition

Illuminating error code p0171 on the dashboard can be frustrating and disturbing for every Chevy owner who suddenly sees it while driving the vehicle. Have you encountered the warning code p0171 on your Chevy vehicle and are looking to fix it and prevent the car from significant issues? The Chevy code p0171 indicates a potential problem related to the air-to-fuel ratio, which is causing the flashing of the fault code.

I will assist you in understanding how you can fix the problem by implementing basic mechanical tasks that are easy for every Chevy owner to perform. Moreover, we will also look at potential causes behind the issue that needs repairing or replacement, what solutions you need to perform to resolve the problem, and what cost you can expect while planning to reach a mechanic to fix the problem. Let’s dive into it.

What is Chevy Code P0171?

The engine needs the correct quantity of air and fuel to function, and it gets power for different actions. When the air-fuel ratio becomes unbalanced, the engine control module (ECM) will deliver a signal to the vehicle computer about the detected issue. In response, the computer system will start flashing the code on the dashboard to inform the driver about the error. 

When the air-fuel mixture becomes too lean (too much air and not enough fuel), it can lead to potential problems such as decreased fuel efficiency, rough acceleration, poor engine performance, and rough idling. That’s why promptly addressing and fixing the Chevy p0171 code is crucial for maintaining vehicle health without being affected by any critical damage.

Most Common Causes of the P0171 Code on a Chevy

Here’s the breakdown of the most common causes of the p0171 code Chevy that are commonly reported while fixing the fault codes.

Vacuum Leaks

The first and most common cause of error codes is vacuum leaks, usually when the vacuum hoses are cracked or disconnected. However, issues with the PCV valve, throttle body, and intake manifold gasket can also cause vacuum leaks, allowing extra air to enter the engine and causing a lean mixture containing too much air and insufficient fuel.

Dirty or Faulty Fuel Injectors

chevy p0171: dirty or  faulty fuel injectors

A fuel injector regulates and monitors fuel injection into the engine’s combustion chamber. When it becomes faulty or dirty, it can disrupt fuel injection, leading to a lean air-fuel mixture and causing the indication of the p0171 code on Chevy’s dashboard.

Faulty Mass Air Flow (MAF) Sensor

The mass air flow sensor is located near the air filter, which tells the computer how much air is entering the engine. When the MAF sensor becomes faulty, malfunctions, or fails to function, it will send incorrect data to a computer, indicating a p0171 code

Malfunctioning Oxygen Sensor

The oxygen sensor monitors the quantity of fuel-air ratio in the combustion chamber. If any unburned fuel or air enters the exhaust system, the oxygen sensor will monitor it and inform the engine control molecule. When it becomes faulty or malfunctioning, it might send incorrect signals to the ECM that will force the engine control module to adjust the fuel mixture improperly.

Dirty or Clogged Air Filter

Dirty or clogged air filters are not a common cause of the Chevy p0171 code, but they can affect the airflow into the engine, leading to a lean mixture. When the air filter is too old and not replaced timely, dust and debris can impact the airflow.

Fuel pump malfunction

The function of the fuel pump is to consistently pump the fuel from the tank to the engine’s combustion chamber. It can disrupt fuel flow to the engine when it fails, bad, or malfunctions. Due to low fuel, a lean mixture is produced, which indicates a warning light on the dashboard.

Low Fuel Pressure

Maintained fuel pressure keeps the air-fuel ratio balanced and helps the engine to function at its peak. When any component that plays a role in delivering fuel fails, such as a faulty fuel pressure regulator, bad fuel pump, or clogged fuel filter, it can cause low fuel pressure. These components can reduce the fuel pressure, impacting the fuel-air ratio and forcing the computer to illuminate warning codes.

Solutions and How to Fix the Chevy Code P0171

After understanding the most common causes, we will explore the solutions that are crucial to implement to fix the Chevy code p0171 fault.

Inspect & repair vacuum leaks.

The first task you must do after encountering the error code is to inspect the vacuum leaks and look at which component is the main culprit behind the leaks. Check the vacuum hoses, gaskets, and intake components thoroughly and repair or replace the cracked, damaged, and faulty components.

Clean or Replace Fuel Injectors

Remove the fuel injector and clean it with a high-quality cleaner to remove the blockage, dirt, and other particles that stop the injector from injecting the fuel into the engine. If it still shows signs of wear & tear, you must replace it and use a new one.

Replace the MAF Sensor

If you find the MAF sensor faulty, you must replace it timely. On the other hand, if the MAF sensor is dirty or clogged, clean it with an MAF sensor cleaner spray after removing it. After ensuring the sensor is cleaned, reinstall it, and then turn the engine to see whether the Chevy p0171 code is fixed and not showing on the dashboard.

Replace the Oxygen Sensor

If the oxygen sensor is malfunctioning, replacing it can fix the issue. For this purpose, remove the old oxygen sensor and install a new one. After installing it, turn the ignition on, and the problem is fixed successfully.

The MAF & oxygen sensors replacement is explained in the video below, which might help you understand easily.

Inspect the air filter.

Check the air filter and see whether it needs replacement or not. If the filter is dirty, clogged, and old, then you must replace it as it’s also very cheap to buy, and you can easily perform replacement yourself without going to any mechanic.

Fuel pump replacement

Inspect the fuel pump condition and seek professional help; professional knowledge and advanced tools are needed. The technician will replace the bad fuel pump to regulate the consistent fuel pumping, which prevents code p0171 Chevy.

Fix Low Fuel Pressure

To fix the low fuel pressure, you must check the fuel filter, fuel pump, and fuel pressure regulator. If any of these components cause low pressure, then that component should be replaced promptly to prevent costly repair.

How much does it cost to fix the p0171 code on a Chevy?

The cost to fix the Chevy code p0171 depends on the cause of the issue. It also can vary with vehicle models, geographic locations, type of shop (dealership or independent), and labor rates in your area. However, the chart below will help you know the average cost to repair or replace the specific component. 

Repair TaskEstimated Cost Range
Vacuum Leak Repair$100 – $200
MAF Sensor Cleaning$10 – $20 (cleaning)
MAF Sensor Replacement$200 – $300
Fuel Pump Replacement$400 – $800
Fuel Pressure Regulator Replacement$150 – $300
Fuel Injector Cleaning$50 – $100
Fuel Injector Replacement$200 – $400
Oxygen Sensor Replacement$150 – $300 per sensor
Exhaust Leak Repair$100 – $200 (minor repair)
Air Filter Replacement$20 – $50

Top Car Brands Frequently Triggering the P0171 Code

Not only do Chevrolet model owners experience the p0171 dtc code, but many other car brand owners also face this error in specific models. Here’s the chart containing popular brands and models whose code is frequently reported.

Car BrandCommon Models Affected
ChevroletSilverado, Malibu, Equinox, Cruze, Impala
FordF-150, Focus, Fusion, Escape, Explorer
HondaCivic, Accord, CR-V, Pilot, Odyssey
ToyotaCamry, Corolla, RAV4, Highlander, Tacoma
NissanAltima, Sentra, Rogue, Maxima, Frontier
BMW3 Series, 5 Series, X5, X3, 7 Series
VolkswagenJetta, Passat, Golf, Tiguan, Beetle
DodgeRam 1500, Charger, Challenger, Durango, Grand Caravan
HyundaiElantra, Sonata, Santa Fe, Tucson, Veloster
KiaOptima, Sorento, Sportage, Forte, Soul

In A Nutshell

The Chevy code p0171 occurs due to the unbalanced air-fuel ratio detected by the computer. Promptly fixing the code is important to prevent the vehicle from poor acceleration, reduced engine performance, and other potential damages. Understanding the common cause, solutions to fix the error, and the average cost of faulty components replacement helps you effectively diagnose the issue, restore Chevy’s optimal performance, and make it run smoothly.

Frequently Asked Questions

What does the P0171 code mean on my Chevy?

The flashing of the p0171 code on Chevy’s dashboard indicates that the air-fuel ratio in bank-1 on the engine is too lean. This means that fuel is low, and too much air is entering the engine, causing fault code p0171 to illuminate.

Can I drive my Chevy with a P0171 code?

Driving with a Chevy code p0171 and not addressing the underlying issues can result in poor performance, engine stalling, hesitation & rough idling, and other significant damages. So, it’s always recommended to fix the p0171 code on your Chevy first and then start driving.

What are the most common causes of the P0171 code in a Chevy?

The common causes that can disrupt the correct air-fuel mixture and lead to lean conditions include:

  • Vacuum leaks.
  • Dirty or faulty fuel injectors.
  • Mass airflow sensor malfunction.
  • Clogged air filters.
  • Bad fuel pumps.
  • Low fuel pressure issues.

How can I fix the P0171 code on my Chevy?

To fix the Chevy p0171 code, the first step is to conduct a thorough diagnosis of possible causes and find the faulty component that is the culprit behind the issue. Then, repair or replace that component and check that the code is fixed successfully. 

How much does it cost to fix the P0171 code on a Chevy?

The cost to fix the p0171 code on a Chevy depends upon specific issues and which component needs replacement. The price ranges from minor replacements like fuel filters to higher replacements or repairs like fuel pumps. After diagnosing which component you need to repair or replace, you can estimate the cost.

Scroll to Top