P0303
PowertrainIgnition Misfirehigh severityCylinder 3 Misfire Detected
What P0303 Means
Misfire detected in cylinder 3.
Symptoms
- Check Engine Light
- Rough idle
- Vibration
- Loss of power
Common Causes
- Worn spark plug #3
- Faulty ignition coil #3
- Faulty injector #3
- Low compression cyl 3
Diagnostic Steps
- Swap coil #3
- Inspect spark plug #3
- Test injector #3
- Check compression
Where to start: Swap coil to diagnose.
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