Cylinder 6 Misfire Detected
The computer detected uneven combustion attributed to cylinder 6. The engine must actually have that cylinder; cylinder 6 requires at least a six-cylinder engine. A misfire code does not distinguish ignition, fuel and mechanical causes. Gasoline spark checks do not apply to diesel combustion. A flashing warning light or severe shaking makes this urgent because continued misfiring can damage exhaust components.
Can I keep driving?
If the engine stalls, the light flashes, shaking is severe, or power loss makes traffic unsafe, pull over safely and arrange towing. With a steady light and normal operation, ask a shop for advice based on symptoms before further driving.
Flashing light, burning smell or smoke? Pull over safely. Danger to life: call 911.
What does this code mean for your car?
The same code can need different checks depending on the model and engine. Enter your vehicle details to find relevant sources and checks.
Symptoms
- Shaking at idle or during acceleration
- Loss of power or stumbling
- Check engine light that may flash
Possible causes
- 1On gasoline engines, cylinder 6 plug, coil or spark-path fault
- 2Cylinder 6 fuel delivery problem
- 3Air leak affecting that cylinder
- 4Low compression or a mechanical valve problem
These possibilities are not ranked by frequency and do not diagnose your vehicle.
Checks you can safely do yourself
Safe checks only: engine off and cold, car on level ground.
- Save the code and freeze-frame data if your scanner offers them, without clearing anything.
- Confirm from vehicle documentation that cylinder 6 exists, and note whether shaking occurred cold, warm or under load without recreating it on the road.
When you need a shop
Have the shop confirm cylinder 6 numbering and examine misfire and injection data, plus ignition on gasoline engines. Compression or leak-down testing may be needed based on findings; the cylinder number alone is not a reason to replace a coil.
How much does it cost?
A US repair estimate needs a diagnosis and a local shop quote.
No verified US repair quote is available for this fault. The price depends on diagnosis, vehicle, parts and local labor; request 2-3 itemized quotes.
Get 2-3 quotes
Investigate this code for my carFAQ
Can I keep driving with P0306?
If the engine stalls, the light flashes, shaking is severe, or power loss makes traffic unsafe, pull over safely and arrange towing. With a steady light and normal operation, ask a shop for advice based on symptoms before further driving.
What can cause P0306?
Possible causes include on gasoline engines, cylinder 6 plug, coil or spark-path fault; cylinder 6 fuel delivery problem; air leak affecting that cylinder; low compression or a mechanical valve problem. These are diagnostic possibilities, not a confirmed diagnosis or a parts shopping list.
Does clearing the code fix the problem?
No. Clearing a code does not repair the problem or prove that no fault exists. It may erase useful evidence and reset readiness monitors. Save codes and freeze-frame data first; confirming a repair requires the vehicle-specific checks.
What if this code appears during a used-car inspection?
Arrange an independent professional pre-purchase inspection before committing. Request a complete scan, readiness status and diagnosis of the relevant system. Get written findings and a repair estimate; an unlit warning lamp does not replace inspection.
How much does a P0306 repair cost?
No verified US repair quote is available for this fault. The price depends on diagnosis, vehicle, parts and local labor; request 2-3 itemized quotes.