{"id":26787,"date":"2026-07-19T17:39:11","date_gmt":"2026-07-19T16:39:11","guid":{"rendered":"https:\/\/www.cathive.co.uk\/advice\/fitting-a-dpf\/"},"modified":"2026-10-01T19:33:52","modified_gmt":"2026-10-01T18:33:52","slug":"fitting-a-dpf","status":"publish","type":"page","link":"https:\/\/www.cathive.co.uk\/nl\/advice\/fitting-a-dpf\/","title":{"rendered":"Een roetfilter vervangen: montage en aanleren in de motorcomputer"},"content":{"rendered":"

Replacing a DPF is two jobs, not one: the mechanical swap, and the electronic set-up that tells the vehicle a new filter is fitted. Skip the second and the car will carry on managing the new filter as if it were the old, nearly-full one \u2014 regeneration never resets, and the new DPF can block within a few hundred miles. The set-up requires diagnostic equipment, which is why a new DPF should be fitted by a competent technician with DPF experience<\/strong>; failing to complete it properly can also invalidate the warranty.<\/p>\n

Before anything else:<\/strong> the old filter blocked for a reason. Work through why DPFs block<\/a> and fix the cause first \u2014 this is the single most important step on this page. Then record the new unit’s serial number (six letters, pin-stamped on the body) before fitting; it’s needed for any warranty query.<\/p>\n

Removal<\/h2>\n
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  1. Let the exhaust cool fully, disconnect the battery earth terminal, and raise the vehicle securely on a ramp.<\/li>\n
  2. Photograph the installed unit for reference \u2014 DPFs often carry several sensors and pipes, and orientation matters.<\/li>\n
  3. Identify every electrical connector and sensor on the unit: differential pressure pipes, exhaust-gas temperature sensors, oxygen sensors. Unplug connectors, free all wiring, and remove sensors carefully \u2014 they seize and are easily broken.<\/li>\n
  4. Loosen all retaining nuts, bolts and clamps; use penetrating oil (or careful heat, with precautions) on anything seized.<\/li>\n
  5. Support the rest of the system and remove the old unit \u2014 DPFs are bulky, so get help if needed.<\/li>\n<\/ol>\n

    Fitting<\/h2>\n
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    1. Clean all mating surfaces thoroughly \u2014 no old gasket material, no corrosion at the joints.<\/li>\n
    2. Use a new fitting kit<\/a> wherever possible; corroded fixings lose thread and length.<\/li>\n
    3. Inspect the rubber differential-pressure hoses for splits, perishing or blockages and renew if in any doubt \u2014 and make sure they go back the correct way round. Best practice is to renew the pressure pipes<\/a> and the differential pressure sensor itself with the new filter; a false pressure reading will quietly ruin it.<\/li>\n
    4. No exhaust paste, no sealant<\/strong> on joints ahead of the DPF \u2014 hardened paste destroys the filter core and voids the warranty.<\/li>\n
    5. Fit the unit loosely first, align it with the rest of the system, then refit the sensors (snug, not over-tight) and reconnect all wiring, routing cables clear of hot surfaces.<\/li>\n
    6. Check clearances all round, then tighten everything fully, taking care not to over-tighten.<\/li>\n
    7. Reconnect the battery, start the engine and check every joint for leaks.<\/li>\n<\/ol>\n

      The ECU set-up \u2014 not optional<\/h2>\n

      With the mechanical work done, connect a capable diagnostic tool and complete the manufacturer’s replacement procedure. Depending on the vehicle this includes:<\/p>\n