The three usual routes
- Forced regeneration — suitable when soot load is high but the filter is not ash-loaded
- Cleaning — considered where ash content is the limiting factor and the filter is sound
- Replacement — where the filter is damaged, melted or beyond cleaning
Why the cause comes first
A filter usually blocks because something else is wrong: failed regenerations, EGR faults, injector condition, sensor errors, oil dilution or a driving pattern that never allows regeneration. Address that and the filter has a chance; ignore it and the new one goes the same way.
What we read before advising
- Soot and ash load values
- Differential pressure across the filter
- Regeneration history and why attempts aborted
- EGR operation and exhaust temperature sensor data
- Oil level and dilution
One thing we will not do
We do not remove or gut filters. It is an MOT failure and illegal for road use. We will tell you the realistic options for your vehicle instead.