P0174

    Get Serviced SoonFix: High — schedule within a week

    System Too Lean (Bank 2) — Same as P0171 but for bank 2. Engine is running lean on the opposite bank.

    Dashboard light triggered

    Check Engine Light

    What to do

    Same approach as P0171 — check vacuum leaks, MAF, fuel delivery. If both P0171 and P0174 are present, the cause is often a common component (MAF, fuel pump).

    Common causes

    • Vacuum leak (shared or bank 2 specific)
    • Dirty or faulty MAF sensor
    • Weak fuel pump or clogged fuel filter
    • Faulty O2 sensor on bank 2

    Estimated repair cost

    $100–$600

    Exact cost depends on the cause, your vehicle, and labor rates in your area.

    What to tell your mechanic

    Use this script so you sound informed and get a clear diagnosis before agreeing to repairs:

    Code P0174, system too lean bank 2. Can you run diagnostics and check for vacuum leaks, MAF, and fuel delivery? I want to understand the cause before any repairs.

    About the Check Engine Light

    Code P0174 triggers the Check Engine Light. Indicates an issue with the engine or emissions system. Could range from a loose gas cap to a serious engine misfire.

    Read full Check Engine Light guide

    Frequently asked questions

    What does OBD code P0174 mean?
    System Too Lean (Bank 2) — Same as P0171 but for bank 2. Engine is running lean on the opposite bank.
    What dashboard light does P0174 trigger?
    P0174 triggers the Check Engine Light.
    How serious is P0174?
    Severity: yellow. Fix priority: High — schedule within a week.
    How much does it cost to fix P0174?
    Repair costs typically range from $100–$600. The exact cost depends on the root cause and your vehicle.

    These codes also trigger the Check Engine Light: