The controller detected crankshaft-speed variation consistent with combustion loss across more than one cylinder.
Why this matters
A trouble code reports a monitored result. It narrows the system and test conditions, but it rarely names the failed part by itself.
Evidence to capture first
- Freeze frame, cylinder counters, fuel trim, coolant temperature, and load
- Ignition secondary evidence and coil power/ground
- Fuel quality, injector balance, intake sealing, compression, and valve timing
A disciplined path
- Confirm which cylinders contribute and when
- Separate ignition, mixture, and mechanical causes with targeted tests
- Check shared inputs or supplies before moving individual parts
- Verify the misfire counters stay stable under the original load
Decision point
The repair is supported when the failed circuit, mechanical condition, or monitored response is measured and the original monitor can run without the fault returning.
Source desk
Use current model-specific service information for specifications, connector locations, disabling procedures, and tightening values. The following public resources support the broader safety or system context used in this guide.
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