DPF Regeneration and Loading
How soot is burned off, why regenerations fail, and how to read soot mass and differential pressure.
Loading…
Safety notice
- Forced regeneration is manufacturer-specific and can be dangerous. Never perform one on a vehicle with fuel dilution, damage or a full DPF without following the procedure.
What you will learn
- Explain passive vs active regeneration
- Read soot mass and differential pressure
- Diagnose a blocked DPF
Advertisement
A diesel particulate filter traps soot, then burns it off. Passive regeneration uses normal exhaust heat; active regeneration raises exhaust temperature on purpose using post-injection or a burner. Both need the right conditions and enough time.
Soot mass and differential pressure readings show how loaded the filter is. A high differential pressure with low soot mass can mean a physical blockage or a faulty sensor. Crucially, a blocked DPF usually has an upstream cause — a faulty injector, EGR or airflow problem that produces too much soot.
Loading…
Key points
- Regeneration requires heat, conditions and time.
- Read soot mass and differential pressure together.
- Fix the soot source, not just the filter.
Loading…
Key points
- Regeneration needs heat and time
- Short journeys prevent regeneration
- A blocked DPF usually has an upstream cause
All values shown are training examples. Real thresholds depend on the manufacturer, engine, temperature and system — always confirm with the vehicle service documentation.
Advertisement