If a vehicle fails inspection because of smoke or elevated particle readings, the cause should be identified first. Depending on the vehicle’s condition, this may require DPF repair, installation of a suitable filter and a check of the engine control software.

Particle readings on a Volvo

The video mentions a Volvo with an earlier reading above 2 million and a later technical-inspection measurement of 45,000. The video does not state the measurement units. It also does not clearly show the inspection’s final result or specify exactly what work was carried out on the Volvo, so the comparison should not be treated as a guaranteed repair outcome.

Toyota without a DPF

One of the Toyota vehicles shown had its DPF cut out. The technician planned to install a DPF and catalytic converter. The installation and a measurement afterwards are not shown, so the outcome of this planned work is unconfirmed.

DPF installation and ECU software checks

If a DPF has been removed or disabled in the ECU, the control software should be checked after a suitable filter is installed, and settings needed for the filter to operate—including regeneration—should be restored. The EGR system and other emissions-control components should also be assessed according to the vehicle’s configuration.

AdBlue/SCR system

AdBlue/SCR faults should be diagnosed by their cause; a warning disappearing does not by itself mean the fault has been repaired. This article does not claim that disabling AdBlue has no effect on vehicle inspection. If the system is faulty or has previously been modified, assess repair options and restoration of its intended operation.