P0301
Cylinder 1 Misfire Detected
Your engine's computer has detected that cylinder number 1 is not firing correctly, meaning it's not contributing power as it should.
The powertrain control module (PCM) has detected a misfire condition in cylinder number 1.
Common causes
- high
Faulty Spark Plug (Cylinder 1)
A worn, fouled, or damaged spark plug in cylinder 1 is a very common cause of a single-cylinder misfire.
Typical part cost: $10-30
- high
Faulty Ignition Coil or Wire (Cylinder 1)
A failing ignition coil or damaged spark plug wire specific to cylinder 1 will prevent proper spark delivery.
Typical part cost: $50-200
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First things to check
- 1Swap spark plug from cylinder 1 to another cylinder and see if the misfire moves.
- 2Swap ignition coil from cylinder 1 to another cylinder and see if the misfire moves.
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Related codes
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Frequently asked questions
How do I find cylinder 1?
Cylinder 1 location varies by manufacturer. For inline engines, it's usually the front-most cylinder. For V-engines, it's typically the front-most cylinder on Bank 1 (the side with the first cylinder in the firing order).
Can a P0301 code be intermittent?
Yes, misfires can be intermittent, especially if caused by a failing ignition coil that acts up when hot, or a partially clogged injector. This can make diagnosis more challenging.
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