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 P1457EVAP Leak P3400VCM Cylinder Deactivation

Not sure where to start?

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