Honda Check Engine Light, decoded

Type your code for a plain-English answer: what it means, the most likely fix, whether it’s safe to drive, and the typical cost.

Find your code

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Misfire & rough run

P0300 misfire · rough idle & shaking

Fuel & air

P0171 lean · MAF & vacuum leaks

Emissions / EVAP

P0420 · P0455–P0457 EVAP · catalytic converter

Sensors

Oxygen (O2) sensor & sensor faults

Most-searched codes

The ones owners look up most.

P0171System Too Lean P0300Random / Multiple Cylinder Misfire P0420P0420 Honda: Causes, Diagnosis & Whether You Can Drive P0430Catalyst Efficiency Bank 2 P0455Large EVAP Leak — Causes & Fix P0456Small EVAP Leak — Causes & Fix P0457EVAP Leak (Loose Fuel Cap) — Fix P0496EVAP High Purge Flow P0497EVAP Low Purge Flow P1457EVAP Leak P145CFuel Tank Pressure Sensor P3400VCM Cylinder Deactivation

Not sure where to start?

Browse every Honda code guide, or jump straight to the one your scanner showed.