OBD-II FAULT CODE
P0300: Random or multiple cylinder misfire detected
CombustionGeneric powertrainThe controller has detected irregular combustion affecting multiple cylinders or without isolating one cylinder.
Possible causes
Examples to investigate; this list is not a probability ranking or a diagnosis.
- Ignition faults on spark-ignition engines
- Fuel delivery or intake leaks
- Compression or valve-timing problems
Symptoms you might notice
- Rough running or shaking
- Loss of power; flashing check-engine light during severe misfire
Diagnostic approach
- If the engine runs badly or the warning lamp flashes, stop safely and arrange diagnosis.
- Read cylinder misfire counters and associated codes.
- Test ignition, fuel delivery and mechanical condition using the vehicle service procedure.
Save codes and freeze-frame information before clearing anything. A cleared warning light does not prove that a repair worked; the applicable monitor must run again.
Possible repairs — after testing
- Repair the verified ignition or fuel fault.
- Correct mechanical faults identified by compression or timing tests.
Related codes
This is general diagnostic orientation, not a manufacturer-specific repair procedure. A qualified technician can confirm test conditions and safe working methods.