StopOrDrive

Enter a 5-character code such as P0420, P0301, or P0457.

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Codes starting with P are engine and transmission, B are body, C are chassis, and U are network communication. A 0 as the second character means a generic code shared by all makes; a 1 means a manufacturer-specific code, so its meaning depends on your brand.

A steady check engine light usually means get it checked soon. A flashing check engine light means an active misfire: reduce speed and stop driving as soon as it is safe.

That doesn't look like an OBD-II code

A valid code is one letter (P, B, C, or U) followed by four characters, for example P0420.

P0302 Cylinder 2 misfire detected

Can I drive with P0302?

Drive soon

OK to drive for now, but get it fixed within days to a couple of weeks, or the damage and the bill can grow.

With a steady light, drive gently and get it checked soon. Misfires waste fuel and slowly damage the catalytic converter.

If your check engine light is flashing, treat this as Stop now: an active misfire dumps unburned fuel into the exhaust and can destroy the catalytic converter within miles.

What does P0302 mean?

Cylinder 2 is not burning its fuel properly, so the engine computer detected that cylinder stumbling. You may feel shaking at idle or a loss of power. Cylinder numbering differs by engine, so check your owner's manual or a diagram for your model to find cylinder 2.

What causes P0302?

Coils and plugs cause most single-cylinder misfires. Move the cylinder 2 coil to another cylinder; if the code changes to match, the coil is bad.

  1. Worn spark plug in cylinder 2
  2. Faulty ignition coil on cylinder 2
  3. Clogged or failed fuel injector for cylinder 2
  4. Vacuum leak near that cylinder
  5. Low compression from a valve or head gasket problem

How much does it cost to fix P0302?

$100 – $600

Spark plugs: $100–$300 at a shop. Ignition coil: $150–$400. Fuel injector: $250–$600. Compression problems cost $1,000 or more. Swapping coils between cylinders to test costs nothing, so always try that before buying any parts. Check the plugs too if they are due.

What are the symptoms of P0302, and how can I confirm it?

Shaking at idle, a stumble when you accelerate, and lower fuel economy are typical. Remove the cylinder 2 spark plug and compare it with the others; a wet, oily, or cracked plug points to the cause. If several cylinders misfire, look for a shared problem such as a vacuum leak.

Will P0302 fail an emissions test, and should I clear it?

It fails any OBD-II based inspection while the light is on. Ongoing misfires also overheat the catalytic converter, which can lead to P0420. After the repair, clear the code and drive normally for a few days. If P0302 comes back, have the injector and compression tested.

Confirm the code yourself

A low-cost scanner lets you read the code, clear it, and see if it comes back before paying for a diagnosis.

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