Catalyst & Fuel-Trim Codes: P0420 / P0430 / P0171 / P0174 Explained | CrankKey

GarageEGR system

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Related: P0136 Meaning — O2 Sensor (Bank 1, Sensor 2) · P0141 Meaning — O2 Sensor Heater (Bank 1, Sensor 2) · P0137 Meaning — O2 Sensor Low Voltage (Bank 1, Sensor 2) · P0420 Meaning — Catalyst Efficiency (Bank 1) · P0430 Meaning — Catalyst Efficiency (Bank 2) · P0171 Meaning — System Too Lean (Bank 1) · P0174 Meaning — System Too Lean (Bank 2) · P0133 Meaning — O2 Sensor Slow Response · P0139 Meaning — O2 Sensor Slow Response (Bank 1, Sensor 2) · Cylinder-misfire cluster (P0300 / P0301 / P0302 / P0303) · EVAP-leak cluster (P0456 / P0442 / P0455) · O2 sensor / MAF cluster (P0101 / P0133 / P0136) · Transmission cluster (P0700 / P0703 / P0720 / P0741) · Fuel-trim cluster (P0171 / P0172 / P0174 / P0175 / P0176) · Browse all OBD-II codes

CrankKey Check engine light guide Contact FAQ P0401 Meaning P0402 Meaning P0403 Meaning P0404 Meaning P0405 Meaning P0406 Meaning Fuel trim Forced Induction Chassis codes C0051 Meaning C0065 Meaning C0085 Meaning C0090 Meaning C0095 Meaning C1651 Meaning C2005 Meaning C2006 Meaning C0472 Meaning C2007 Meaning C0473 Meaning C2417 Meaning C0495 Meaning ABS / chassis codes ABS codes ABS solenoid codes EPB codes Restraint / SRS codes Wheel-speed sensor codes Codes by cluster P0420 Meaning Powertrain codes Ignition & misfire codes P0421 Meaning Trending fixes Catalyst codes Emissions codes O2 sensor codes