30/06/2026 8:38 am
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Passat TDI P2002 returns even though calculated soot is low after regeneration
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A 2014 Passat TDI completes commanded regenerations and calculated soot falls to 7 g, but differential pressure remains high at elevated RPM. Ash accumulation is reported near its service limit, exhaust-temperature sensors agree and pressure hoses are clear. P2002 returns after highway driving.
Can another regeneration help, or does the remaining restriction point to ash that cannot be burned off?
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01/07/2026 9:35 am
Regeneration oxidizes soot; it does not remove mineral ash. First prove the pressure sensor zero and hose path, then compare measured restriction with the model's ash-load and mileage criteria. If soot calculation is low, temperatures were achieved and restriction remains above specification, repeated regeneration adds heat without addressing ash.
Follow the approved DPF cleaning or replacement decision for that vehicle and reset learned values only after the physical service. Inspect the cause of excessive ash or oil consumption so the replacement is not treated as a standalone fix.
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02/07/2026 7:25 am
An independent manometer confirmed the high restriction, and ash load was beyond the service threshold. The approved DPF replacement and adaptation reduced pressure to specification. The next passive regeneration completed without P2002.