Positive fuel trim and hesitation followed unmetered air entering through a poorly seated duct after prior service.
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
- Fuel trim by rpm
- MAF plausibility
- Duct fit and clamp position
- Smoke at the service joint
A disciplined path
- Inspect recent work
- Compare trim patterns
- Confirm the leak
- Reseat the duct, replace only damaged service parts, and verify
Decision point
Normal trim and load response after resealing ruled out the proposed MAF replacement.
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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