Cause
Blocked diesel particulate filter
A particulate filter restricted to the point that it obstructs the engine's exhaust, rather than one merely carrying a normal load of soot awaiting its next regeneration. That distinction is the whole of this entry, and it decides whether the repair is a drive cycle or a new filter. Soot is combustible and burns away during regeneration; ash is not, and it accumulates for the life of the filter.
A blocked filter presents as a power loss that worsens with load, because the engine is pumping against a restriction that grows with flow. Boost falls short of target even with a healthy turbocharger, exhaust temperatures rise, and the turbocharger's own codes may appear first — which is why this cause sits on boost and temperature codes rather than only on filter codes.
Ash-blocked is the end of the filter's service life and is not a fault. It arrives after a high mileage of normal use, mostly from engine oil additives. Soot-blocked before that mileage is a symptom of something else — repeated short journeys that never allow regeneration, a fault that has been aborting regenerations, or an injector or turbocharger fault making far more soot than the filter was designed for. Replacing the filter without finding that cause replaces it again, so read the stored regeneration history before ordering the part.
Typically specialist work. Needs equipment or training most home workshops do not have.
Some of these codes mean you should stop driving
3 of the 5 codes this can cause indicate a fault where continuing to drive risks damage or is unsafe. Which one you have matters more than the cause does — read the code's own page before deciding.
Codes this can cause (5)
Codes where this is a likely explanation first, rather than merely a possible one.
- P2263 Turbocharger/Supercharger A Boost System Performance High
- P2428 Exhaust Gas Temperature Too High Bank 1 Stop driving High
- P2429 Exhaust Gas Temperature Too High Bank 2 Stop driving High
- P2579 Turbocharger/Supercharger Speed Sensor A Circuit Range/Performance Stop driving High
- P2698 Exhaust Aftertreatment Fuel Injector A Performance High
Information, not instruction
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Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
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