What is P0171

Fault code P0171 indicates the engine is running to lean on bank number one, indicating either two little fuel or no fuel at all.

What is meant by Bank 1?

Bank 1 refers to the air in an engine, often divided into two banks. In V-shaped engines, it is usually on the driver’s side, indicating an issue with one of the cylinders. Inline six engines typically have two banks, referring to cylinders number one, two, and three. Inline 4 engines may not have two banks, but often use two engine banks, typically cylinders number one and two. This code P0171 is used to identify issues with the engine.

Reasons for P0171

P0171 is a common fault code in a system that leans towards one side, often due to faulty fuel injectors, weak fuel pumps, vacuum leaks, exhaust leaks, and sensor issues, particularly oxygen or mass airflow sensors. Other potential causes include vacuum leaks, exhaust leaks, and other potential issues

Symptoms of P0171

P0171 symptoms include check engine light, power loss, rough idle, stuttering, hesitation, engine misfires, separate fault code, and a vehicle being thrown into limp mode, limiting power and speed. The cause depends on the vehicle’s limp mode.

P0171’s level of severity

Engine F code P0171 is a severe fault that can be dangerous when the engine is running lean. Proper fuel and air levels are crucial to avoid engine knocks and detonations, which can cause catastrophic failure. If you have F code P0171, be cautious with the throttle running lean at idle or low loads. Driving aggressively or spiritedly can increase the risk of engine damage. If you have P 0171, limit driving and be cautious on the throttle. The best bet is not to drive until the problem is solved, but to drive gently if necessary.

Examinations

Diagnostics for fault code P0171 can be straightforward if you have the right tools and experience. If you’re not experienced, it may be more complex and require a repair shop. To diagnose the issue, first check if you’ve already scanned the computer or ECU for these engine codes. It’s also important to understand any other fault codes you’re receiving, such as O2 sensor issues or Lean Bank 2 issues.

for example

Faulty fuel injectors can affect one cylinder unless two on different banks fail or get clogged at the same time. If the system leans on both banks, it may be a problem with a fuel pump, fuel pressure regulator, or fuel pressure sensor. If p0171 is the only fault code, test for vacuum leaks using a vacuum gauge with the engine off. If fuel pressure is good, test mass air flow and oxygen sensors. If the issue is not with the fuel injector, an engine misfire can be identified. If necessary, a repair shop may be the best bet. Most causes of fa code P0171 are relatively inexpensive, with parts ranging from $10 to $150 depending on the issue. Repair bills for one or two hours of labor can add $100 to $300 to the total bill.