P0309
PowertrainIgnition Misfirehigh severityCylinder 9 Misfire Detected
What P0309 Means
Misfire detected in cylinder 9.
Symptoms
- Check Engine Light
- Rough idle
Common Causes
- Worn plug #9
- Faulty coil #9
- Faulty injector #9
Diagnostic Steps
- Swap coil
- Inspect plug
- Test injector
Where to start: Diagnose cylinder 9.
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