P0303: Cylinder 3 Misfire Detected
System: Engine misfire · Priority: high
What P0303 means
The control module detected a condition matching the generic definition Cylinder 3 Misfire Detected. A trouble code identifies what the module detected; it does not automatically identify the failed part.
Useful next checks
- Check ignition and injector operation on cylinder 3.
- Review misfire counters and freeze-frame data.
- Consider compression/leak-down testing if ignition and fuel checks pass.
Why vehicle context matters
The same generic code can have different diagnostic paths depending on engine, calibration, wiring layout, service bulletins and related codes. Freeze-frame and live data can help establish when the fault occurred.
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