What is P0171 code for BMW?
What is P0171 code for BMW?
When a vehicle has the fault code P0171, it means that computer can no longer automatically adjust the mixture between air and fuel. Code P0171 applies to 4-cylinder engines (Bank 1) as they generally have only one bank. If you have a V6 or V8 engine you can also get a P0174 code which refers to Bank 2.
What causes P0171 and P0174 codes BMW?
A P0171 or P0174 trouble code can happen because of a vacuum leak or faulty sensor. Vacuum leak faults usually—not always—manifest more readily at lower speeds; as a rough idle, for example. A capable scan tool can check fuel trim values at idle and at higher engine speeds and detect when the lean condition occurs.
What causes system too lean code?
The lean condition can be caused by a vacuum leak, which introduces more air into the air-fuel mixture, or by a weak fuel system, which does not input enough fuel into the air-fuel mixture.
What to do if your BMW has a p0171 code?
If there are no intake leaks, the next step is to replace the air filter and clean the air flow meter. If the problem persists the front oxygen (O2) sensor may need to be replaced. The cost to diagnose the P0171 BMW code is 1.0 hour of labor.
What does the p0171 code on bank 1 mean?
Code Definition. P0171 – System Too Lean (Bank 1) What does the P0171 code mean? The P0171 code means that the Oxygen (O2) sensor on bank 1 recognized a too lean mixture to correct it. The Oxygen O2 sensors have the ability to correct a fuel mixture of +-15%. If it needs to correct the air-fuel mixture more than that, the P0171 code will be stored.
Can a faulty MAF sensor cause a p0171 code?
If you start replacing MAF sensors, O2 sensors, etc., you will probably spend a lot of money without results. A faulty O2 sensor is not a very common cause of the P0171 code, even if many people start to replace it directly when they see this code.
How is the p0171 code stored in the oxygen sensor?
The Oxygen O2 sensors have the ability to correct a fuel mixture of +-15%. If it needs to correct the air-fuel mixture more than that, the P0171 code will be stored.