P0171 — System too lean (bank 1).

Code P0171 is a standard OBD-II diagnostic trouble code: System too lean (bank 1).

In ProblemsByVin's analysis of the NHTSA owner-complaint record, owners cite P0171 across 52 vehicle failure patterns. Diagnostic codes in complaints are reported by owners and are unverified — they point to where this code shows up, not a confirmed diagnosis. Open a page below for the full pattern (symptoms, mileage, repair costs owners cite).

Vehicles where owners report P0171 52 patterns

2022 Toyota RAV4

electrical — Water ingestion causing engine stall and loss of electrical power

2021 Kia Seltos

engine — Engine stall and loss of power at low speeds and highway speeds

2021 Kia Soul

powertrain — Defective piston oil rings with engine seizure risk

2020 Chevrolet Traverse

engine — Front exhaust pipe bracket cracking and weld failure

2020 Ford Escape

powertrain — Transmission failure — complete breakdown and repeated replacement

2020 Ford Escape

fuel system — Fuel-injector failure

2020 Honda HR-V

powertrain — CVT transmission fluid degradation and internal wear

2020 Jeep Compass

powertrain — Cylinder head gasket failure & combustion gas ingress

2019 Chevrolet Trax

engine — Cooling system failures and overheating

2018 Buick Encore

powertrain — Turbocharger failure and recurring breakdown

2018 GMC Terrain

powertrain — Check Engine Light & P0171 Code (System Too Lean)

2018 Toyota Camry

engine — Stalling and Loss of Power While Driving

2018 Toyota Corolla

fuel system — Engine stalling during driving

2017 Chevrolet Trax

engine — Oil leak from turbocharger return line and fractured internal tube

2017 Dodge Journey

powertrain — Fuel pump pressure loss & failure

2016 Subaru Legacy

electrical — Oil intrusion into electrical components (ECU and O2 sensors)

2015 Chevrolet Cruze

engine — Engine stalling and loss of power without warning

2015 Dodge Journey

electrical — Engine stall at highway speed with loss of steering, brakes, and throttle

2014 Chevrolet Malibu

engine — Rough Idle / Engine Misfire / Stuttering

2014 Jeep Compass

engine — Throttle body failure

2014 Kia Sorento

engine — Excessive oil consumption

2013 BMW 328i

electrical — Valve Cover Leak and Electrical Misfire

2013 Chevrolet Sonic

electrical — Emission codes and component replacement failures—recurring faults

2013 Chevrolet Sonic

engine — Acceleration surge, jolting, and rough running at idle

2013 Chevrolet Sonic

powertrain — Intake Manifold Gasket Failure Leading to Fuel and Drivability Issues

2013 Chevrolet Traverse

powertrain — Sudden loss of power / limp mode activation

2013 GMC Terrain

electrical — Instrument Panel Electrical Shorts and Gauge/Warning Light Failure

2013 Lincoln MKZ

powertrain — Hard shifts and rough transmission behavior

2013 Subaru Outback

engine — Excessive oil consumption

2013 Subaru BRZ

engine — Catastrophic engine failure after valve spring recall

2012 Chevrolet Cruze

engine — Oil leaks from valve cover, oil pan, and gaskets

2012 Chevrolet Sonic

engine — Check engine light and emission system faults

2012 Hyundai Veloster

engine — Excessive oil consumption / internal oil burn

2012 Subaru Outback

brakes — Brake booster failure

2012 Subaru Forester

engine — Excessive oil consumption

2011 Chevrolet Cruze

cruise control — Loss of engine power / limp mode

2011 Toyota Corolla

cruise control — Abnormal deceleration / failure to slow when accelerator released

2007 Chevrolet Silverado

powertrain — Electrical loss of power and instrument cluster failures

2007 Toyota RAV4

cruise control — Brake booster failure—loss of vacuum, soft pedal, inability to stop

2007 Toyota Camry

brakes — Brake Actuator Assembly Failure

2007 Toyota Corolla

engine — Engine Control Module (ECM) Failure – Cracks in Solder Points

2006 Chevrolet Trailblazer

electrical — Widespread electrical system faults and sensor codes

2006 Chevrolet Corvette

engine — O2 sensor failures and fuel mixture issues

2006 Chevrolet Equinox

powertrain — PCM (Powertrain Control Module) failure

2006 Ford F-150

engine — Exhaust Manifold Stud Failure and Warping

2006 Ford Ranger

engine — Cylinder Head Exhaust Valve Seat Recession

2006 Volkswagen Passat

brakes — Brake vacuum hose cracking or failure

2005 Chevrolet Cobalt

engine — Reduced engine speed and engine disabled warnings

2005 Ford F-150

engine — Engine stalling and loss of power (intermittent)

2005 Jaguar S-Type

fuel system — Fuel tank leaking during and after refueling

2005 Toyota Corolla

engine — Engine Stalling (ECM-related)

2005 Toyota Corolla

fuel system — O2 sensor malfunction and lean running condition

Codes are pulled from what owners wrote in their NHTSA filings — they're allegations, not a shop diagnosis. Always confirm with a live scan. Browse all diagnostic codes →