The P0171 trouble code indicates that the air-fuel mixture is too lean in bank 1. This code typically points to issues related to the engine receiving too much air or too little fuel, leading to potential operational problems or damage to the engine components.
System Too Lean (Bank 1)
Code symptoms P0171.
1. Engine hesitation or stumbling.
2. Decreased fuel efficiency.
3. Malfunction indicator light (MIL) illumination.
This code is common in brands such as:: Chevrolet, Renault, Ford, Toyota, Nissan, Mercedes Benz, Honda.
Causes of the code P0171.
1. Vacuum leaks in the intake manifold or vacuum hoses.
2. Faulty mass air flow (MAF) sensor.
3. Issues with the fuel delivery system or fuel pressure.
Code Solutions P0171.
1. Inspect and repair any vacuum leaks in the intake manifold or hoses.
2. Clean or replace the mass air flow (MAF) sensor if it is faulty.
3. Check and ensure proper function of the fuel delivery system and fuel pressure.