Common Symptoms
- DPF regeneration takes excessively long to complete
- Frequent DPF regeneration cycles
- Increased fuel consumption during regeneration
- Check engine light illuminated
- Reduced engine power or performance
- Exhaust temperature warning light may appear
Most Likely Root Causes
- Restricted or clogged diesel particulate filter
- Faulty differential pressure sensor
- Malfunctioning exhaust temperature sensors
- Fuel injector issues affecting post-injection
- Excessive oil consumption contaminating DPF
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Component Location
The diesel particulate filter is located in the exhaust system downstream of the turbocharger and typically before the SCR catalyst.
Manufacturer Notes
Some manufacturers require specific driving conditions or forced regeneration procedures to properly diagnose extended regeneration duration issues.
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