What does system Lean Bank 1 mean?

The OBDII trouble code P0171 – System Too Lean (Bank 1) means that the engine air-fuel mixture is too lean, or there is too much air and too little fuel. Driving a car with the code P0171 can cause more damage to the engine over time, as when the engine runs lean, the combustion temperature is higher.

Why is my check engine light still on after changing o2 sensor?

The check engine light could be caused by more than one problem. Your oxygen sensor may have been replaced by the technician, but your spark plugs need to be replaced as well.

Can bad fuel injectors cause car to run lean?

Your engine runs lean if your air-to-fuel mixture is too light – this means that the fuel in your ignition chamber is being igniting with too much air or too little fuel. Your engine running lean is always a symptom of another problem – it could be a dirty MAF sensor, a damaged oxygen sensor, or damaged fuel injectors.

What causes the system too lean in bank 1?

What are the causes of the system too lean in bank 1 (P0171 code)? The shorter-term for the system is too lean in bank 1 is code P0171. This code means that the system is running weakly on the first engine bank and is unable to properly deliver the correct amount of fuel to power the engine.

What causes p0171 fuel system Lean Bank 1?

Another thing that can cause your p0171 lean code would be incorrect valve timing. It sounds strange, but if the valve timing has jumped, then the intake valve or valves for each cylinder will not stay open as long as they should while the piston is moving down.

What does it mean when your engine is too lean?

System Too Lean (Bank 1) What the P0171 code means The P0171 OBD-II code means that, on the first bank of the engine, the fuel system is running weak or a vacuum leak exists near this side of the engine. A lean condition occurs when the engine either receives too little fuel or too much air.

Can a low fuel pressure cause an engine to run lean?

Low fuel pressure can certainly cause the engine to run lean which will obviously flag a P0171 lean code. However, I do not see this one very often causing this code.