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P0307

Cylinder 7 Misfire Detected

Your engine is not burning fuel correctly in cylinder 7. This can cause rough running, poor power, and damage to the catalytic converter if driven too long.

Severity4/5 High
Can I drive?⚠ With caution

You may be able to move the vehicle short distances, but driving with an active misfire can damage the catalytic converter and may worsen engine damage. If the engine is shaking badly, flashing the check engine light, or losing power, stop driving and diagnose it right away.

DIY
$20–$250
Shop
$150–$800
Difficulty
intermediate

What It Means

P0307 means the engine computer has detected a misfire on cylinder 7. The misfire may be occasional or continuous, and the cause can be ignition, fuel delivery, air leak, compression, or wiring related. If the misfire is severe, the ECM may flash the check engine light to warn of possible catalytic converter damage.

Symptoms

Common Causes

1. Faulty spark plug in cylinder 7high
2. Bad ignition coil or coil boot on cylinder 7high
3. Fuel injector problem on cylinder 7medium
4. Vacuum leak or intake air leak affecting cylinder 7medium
5. Worn or damaged spark plug wire or connector, if equippedmedium
6. Low compression from worn engine components, leaking valve, or head gasket issuemedium
7. Dirty or contaminated fuellow
8. Wiring, connector, or ECM driver issue for cylinder 7low

Related Codes

FAQ

Can I keep driving with P0307?

Only for short, cautious trips if the engine runs normally and the light is not flashing. If it is shaking, losing power, or the light is flashing, stop driving and diagnose it immediately.

What is the most common cause of P0307?

A worn spark plug or a bad ignition coil on cylinder 7 is usually the first thing to check.

Will P0307 go away on its own?

Sometimes the code may clear temporarily, but the underlying problem usually remains and the misfire can return.

Can a bad injector cause P0307?

Yes. If cylinder 7 is not getting the right amount of fuel, it can misfire and set this code.