This Mitsubishi diesel could not pass its roadworthiness inspection because of excessive smoke opacity. Work had already been carried out at another garage before the vehicle came to AutoChip, but the smoke level still prevented it from passing.

AutoChip checked the vehicle and worked on the software to adjust its operation and reassess smoke opacity. A further smoke test was carried out after the work, and the video reports that the test was passed.

The exact final reading and a detailed list of the work are not provided in the video. The result therefore confirms only that the smoke test shown was successful; it does not, by itself, prove that every possible engine or exhaust-system fault has been repaired.