P0171 OBD Error Code: Problem & Solutions

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Is there an illumination in your check engine light and it is reading error code P0171? What does it mean? There are a lot of people who make mistake by considering oxygen sensor to be bad. But in reality, the oxygen sensor is not bad. The P0171 fault code would mean that there is incorrect ratio of air and fuel on the car’s engine system

It is the powertrain control module of the car which monitors the fuel delivery system adaptive fuel strategy to ensure perfect condition on the engine at favourable air-fuel ratio of 14:7:1. The injector pulse is adjusted automatically by the computer which would help in regulating the amount of fuel that is sent to the engine. The information is then relayed by the oxygen sensor to the computer and uses it to regulate how much amount of fuel is needed.

What causes this problem with the System too Lean (Bank 1)?

• There can be some faults in the fuel pressure regulator
• The fuel pump might be weak
• A fuel filter can get clogged
• Defective powertrain control module
• Leakage in the vacuum
• There can be some faults in the injector
• Some faults with the car oxygen sensor
• Default in the mass air flow sensor

1. Oxygen Sensor - P0171 error code also relates to problems with the Oxygen Sensor. Find top notch Oxygen Sensor with us.
2. Vacuum - OBD Error Code P0171 can simply be due leakage in the vacuum. Replace old and damage components now!
3. Fuel Injector - If there is any fault detected in the Fuel Injector, and flash OBD Code P0171. Replace faulty Injector now!
4. Mass Air Flow (Maf) Sensor - Faulty Mass Air Flow (Maf) Sensor can give rise to P0171 fault code. Replace faulty Mass Air Flow (Maf) Sensor immediately.
5. Powertrain Control Module - Faulty/damaged VVT Powertrain Control Module can cause a lot of issues. Thus, it is important to replace it immediately.
6. Catalytic Converter - Problematic Catalytic Converter can give rise to P0171 fault code. Replace faulty ECM components immediately.
7. Fuel Pump - OBD Code P0171 can flash if the Fuel Pump is damaged. You must replace it with a brand new one online with us.
8. Fuel Filter - P0171 code can display due to some issues with the Fuel Filter. So, it is very important to replace the Fuel Filter with us at equitable prices.
9. Fuel Pressure Regulator - Do you remember when was the last time you got your car Fuel Pressure Regulator inspected? A damaged Fuel Pressure Regulator can cause a lot of issues like displaying P0171 code.

We at Parts Avatar Canada care for our customers, and that’s why we will help you to diagnose P0171 code by listing out some major symptoms. They are mentioned below as follows:

Common Symptoms

• There can be loss of power
• Check engine light can start illuminating
• The issue of hesitation or stumble from the engine
• There can be a difficulty in starting the car engine
• Issue of car engine dying
• Catalytic converter damage may result if this code is stored for a long period of time

It is very important to fix the fault code P0171. So here are some ways with which you can correct this issue:

• The fuel pump should be replaced
• Make sure that you replace the fuel filter
• Make sure that you replace the fuel pressure regulator
• Issues with the powertrain control module can give rise to this fault code, so it should be replaced
• Restore one or more injectors
• You can always one or more oxygen sensors
• The mass air flow sensor should be replaced carefully
• The vacuum leak should be repaired

However, if you face any issue then we have stocked a wide range of best priced O2 sensor, air flow meter, mass air flow sensor cleaner and more to help you out in fixing your car.

If the fault code P0171 is detected, then it would mean that the computer can now not automatically adjust the mixture which is between the air and fuel. The trouble code P0171 would apply to 4-cylinder engines bank 1 as they normally have only one bank. If you have a V6 or V8 engine, then P0171 can also trigger which would refer to bank 2

If the code says that the fuel system is “too lean”, then it would mean that the computer has been adding more and more fuel which is known as Long Term Fuel Trim. The Long-Term Fuel Trim should be close to 1 to 2 percent. If the code P0171 code start appearing, then it would mean that the fuel trim is anywhere from the 15 percent to as high as 35 percent. If this happens, then the computer would know that there is an improper condition in the control of the fuel system

The first thing which you should do while diagnosing the P0171 fault code is to look at a minimum of three ranges of the Long-Term Fuel Trim numbers on a scanner. The idle reading should be checked – 3000 RPM uploaded and 3000 RPM with at least 50 percent load. After that you must check the freeze frame information for the code to check which ranges have failed and what the operating conditions are.

Common Mistakes When Diagnosing The P0171 Code

A lot of people do not search for technical service bulletins for your specific car model while diagnosing the P0171 fault code. One thing which should be kept in mind is that every code would not have technical service bulletin associated to it, but it would be a great idea to check as it would save a lot of your time as well as precious effort.

P0172 - System too Rich (Bank 1)

P0174 - System too Lean (Bank 2)

P0175 - System too Rich (Bank 2)