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.

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Misfire & rough run

P0300–P0308 · 9 guides

Fuel & air

P0171, P0174, MAF/MAP · 7 guides

Emissions / EVAP

P0420, P0455, P0456 · 8 guides

Sensors

O2, MAF, MAP, knock · 6 guides

Transmission

P0700, P0740 · 5 guides

Electrical

U0100, battery, charging · 6 guides

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P0171System Too Lean P0300Random / Multiple Cylinder Misfire P0420P0420 Honda: Causes, Diagnosis & Whether You Can Drive

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