All coils were replaced even though the misfire remained on one cylinder and a mechanical sealing test had not been performed.
Why this matters
The value of this case is the order of evidence and the verification step. The same symptom on another vehicle may have a different cause.
Evidence to capture first
- Cylinder counter
- Coil and plug swap result
- Injector command
- Relative compression and leak-down evidence
A disciplined path
- Return to the original complaint
- Use swaps only as controlled A/B tests
- Check compression when the fault does not move
- Repair the measured mechanical cause
Decision point
A part swap that does not move the fault is evidence against that part.
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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