This case is based on a BMW diesel investigated at BEM-TEC. The vehicle identifiers have been removed and the image is illustrative.
A new DPF does not fix the root cause
The particulate filter had already been replaced, yet it became clogged again. Diagnostics found a glow system fault, an EGR system malfunction and an air-mass measurement fault. Each can affect whether regeneration takes place under the right conditions.
What should be checked before another regeneration?
- engine management fault codes and stored operating conditions
- glow system operation
- EGR and air-mass measurement
- exhaust back pressure and DPF load data
- engine temperatures and regeneration conditions
Why investigate first?
If the underlying fault remains, even a new or cleaned DPF may become overloaded again. That is why we work from the symptom towards the root cause before replacing parts or repeatedly forcing regeneration.