Fuel Trim Analyzer
Interpret STFT and LTFT patterns to separate vacuum leaks, MAF issues, fuel pressure problems and rich conditions.
Interactive preview
Rule-based guidance, not a final repair diagnosis.
Suggested direction
Positive trims on both short and long term suggest unmetered air, low fuel pressure, dirty MAF data, or an exhaust leak before the upstream O2 sensor. Start with an intake smoke test and MAF review.
This tool helps prioritize checks. Safety-critical symptoms, fuel leaks, brake faults and flashing check engine lights should be inspected by a qualified technician.
How to use this tool safely
- Save the original code and freeze-frame data before clearing anything.
- Use the result as an inspection order, not as proof that a part is bad.
- Confirm power, ground, signal, vacuum, pressure or mechanical condition before replacing expensive parts.