EZCarFix DIY Auto Repair

BMW 3-Series · Diagnostic Trouble Code

P0171 — System Too Lean (Bank 1)

Quick overview of P0171 on your BMW 3-Series. Read the full diagnosis guide, then find the repair guides for your vehicle below.

Read the full P0171 diagnosis guide →

Repair guides that fix P0171

BMW 3-Series

2019-2023 BMW 3 Series - Engine Air Filter Replacement

A restricted air filter can skew the air-fuel mixture.

BMW 3-Series

2012-2018 BMW 3 Series - Check Engine Light / OBD2 Diagnosis

What that light means and what to check first.

General diagnostic information, not a factory service procedure. If you're unsure, have a qualified technician confirm the diagnosis before buying parts.