Random or multiple-cylinder misfire detected
The controller detected crankshaft-speed variations consistent with misfire across multiple or non-fixed cylinders.
Conditions that can produce P0300
These are diagnostic branches, not a ranked parts list. Prevalence and testing order depend on the exact vehicle and failure scene.
- Ignition energy or plug problem
- Fuel quality, pressure, or injector issue
- Air leak or EGR distribution problem
- Compression, valve timing, or internal mechanical fault
- Voltage, ground, sensor, or calibration issue
What to inspect next
- Reduce load and stop safely if the lamp flashes or the engine shakes severely
- Preserve cylinder counters and freeze-frame conditions
- Determine whether the pattern is bank, cylinder, load, temperature, or fuel related
- Use controlled ignition, injector, compression, and leakage tests
Evidence that strengthens the answer
Verify the repair
Preserve the pre-repair record, document exactly what changed, then repeat the relevant operating condition safely. Confirm no current or pending fault returns, review permanent-code and readiness state where applicable, and state which tests or modules remained unavailable.
This page explains a commonly standardized code at a general level. Confirm the exact definition, module, status, test conditions, thresholds, wiring, and service process for the vehicle application using current official information.