The BMW 118d had four larger injectors from a BMW 535d, while the turbocharger and intercooler remained standard. According to the video, the DPF, catalytic converter and EGR system were absent. An earlier software tune had already produced approximately 186 hp and 437 Nm, but the setup generated considerable smoke.

AutoChip revised the existing file, adjusting the fuel-delivery strategy to reduce smoke. After calibration, the dyno recorded around 190 hp and 477 Nm. The aim was to retain strong power and torque while reducing some of the smoke associated with the previous calibration.

The technician notes that with the standard turbo and intercooler, maximum output with no smoke at all may not be achievable. A larger intercooler could provide more airflow for further calibration, but it was not installed as part of this work.