Diagnostic Trouble Codes/ Error Code- VW/Audi/Skoda

P0171: System too lean (bank 1)

"P0171: System too lean (bank 1)" is a diagnostic trouble code (DTC) that is commonly found in Audi and other vehicles. The code indicates that the engine management system has detected an excessively lean air/fuel mixture in bank 1 of the engine.

An air/fuel mixture that is too lean means that there is not enough fuel in the mixture compared to air, which can cause a variety of problems. Some of the common causes of this code include:

• A vacuum leak in the intake system
• A clogged or dirty air filter
• A failing mass air flow (MAF) sensor
• A malfunctioning fuel injector
• A leaking fuel pressure regulator

It is important to diagnose and repair the cause of the P0171 code to ensure the proper operation of the engine and prevent further damage. A proper diagnosis should be performed by a qualified mechanic or dealership service center.