Misfire codes (P03xx)
One or more cylinders not firing cleanly. Common signs: rough idle, shaking, hesitation on acceleration, poor fuel economy.
Important: Content here is general information only, not professional mechanical advice or a diagnosis for a specific vehicle. When in doubt, have a qualified mechanic assess it promptly.
- P0300: Random/Multiple Cylinder Misfire Detected — The engine computer has detected misfires happening across multiple cylinders rather than one specific cylinder — the engine is not firing cleanly on all cylinders.
- P0301: Cylinder 1 Misfire Detected — The engine computer has detected misfires specifically in cylinder 1 — that cylinder is not firing cleanly while the others are.
- P0303: Cylinder 3 Misfire Detected — The engine computer has detected misfires specifically in cylinder 3 — that cylinder is not firing cleanly while the others are.
- P0305: Cylinder 5 Misfire Detected — The engine computer has detected misfires specifically in cylinder 5 — that cylinder is not firing cleanly while the others are.
- P0306: Cylinder 6 Misfire Detected — The engine computer has detected misfires specifically in cylinder 6 — that cylinder is not firing cleanly while the others are.
- P0302: Cylinder 2 Misfire Detected — The engine computer has detected misfires specifically in cylinder 2 — that cylinder is not firing cleanly while the others are.
- P0304: Cylinder 4 Misfire Detected — The engine computer has detected misfires specifically in cylinder 4 — that cylinder is not firing cleanly while the others are.