Tag Archives: Diesel Particulate Filter

Before you fit a new Diesel Particulate Filter (DPF)…

Before you fit a new Diesel Particulate Filter (DPF)…

Have you considered the following?

• Have you compared a picture of the faulty DPF with a picture of the replacement DPF?

• Check the vehicle history for any existing issues.

• Have a copy of the DPF Fitment Guide for the Professional – available from your local DPF supplier.

• Confirmed the reason for the apparent DPF failure, e.g. engine issues, injector timing, DPF pressure or flow, air leak, EGR, heater or glow plug, turbo engine wear.

• Inspect intercooler & associated plumbing for leaks or wear.

• Replaced the engine oil and filter, use low ash factory oil only.

• Check the used oil for any sign of contamination (thinning due to over fuelling/large clumps of carbon).

• Check the fuel for any signs of contamination e.g. water, bio-fuel or solids. Ensure low sulphur fuel only is being used.

• Ensure NO Bio-fuel has been used.

• Check catalytic converter efficiency, are there any signs of damage, heat discolouration or pitting of the substrate.

• Check all pressure and temperature sensors on the DPF.

• Purchase a new DPF fitment kit including gaskets, bolts and mountings.

• Ensured that no exhaust paste or silicone sealant is being used upstream of the DPF or Catalytic Converter.

• Re initialise Engine Control Units, reset ash level & adaptations and where necessary complete Engine Control Module restore.

• Check for vehicle Engine Control Module programming updates.
Check Adblue or Eolys (if applicable) at sufficient level.

• Completed a successful Forced Regeneration before driving the vehicle.

What is a DPF and What to check when replacing.

What is a Diesel Particulate Filter (DPF) ?

A Diesel Particulate Filter (DPF) is a device designed to remove diesel particulate matter or soot from the exhaust. Unlike a Catalytic Converter, a DPF is not a flow through device. Exhaust gases are cleaned by passing through the walls of the DPF leaving particulate matter to accumulate on the inlet face of the DPF. Once the DPF reaches a certain level it must be cleaned. Through filter “regeneration” these soot particles are burnt off at high temperatures.


Advice for DPF care

– When the DPF warning light illuminates you must follow the instructions in the owners manual immediately. Failure to comply could lead to a blocked DPF.

– Active DPF’s that use an additive fluid to assist in the regeneration process must never be driven without this fluid, as this could lead to a blocked DPF.

– When fitting a new active DPF or topping up the additive, the control unit must be reset to New DPF / Refilled Additive. (See Zetti DPF Tool section)


– It is not advisable to run a DPF vehicle on biodiesel.

– Always check the engine oil for diesel contamination, which can occur during the regeneration process. If the oil is contaminated then the engine oil and filter must be replaced.

What to check when replacing the DPF

Follow these steps when replacing a DPF:
  1. Ensure the root cause of the problem is rectified before replacing a DPF
  2. Use new mounting brackets
  3. Line up the DPF perfectly to avoid vibrations or anomalies in exhaust pressure
  4. Don’t hit the DPF with hammers or other rigid tools to avoid the monolith from breaking
  5. Do not use exhaust paste on the DPF
  6. Replace the engine oil of the vehicle
  7. Update the engine management software to tell the vehicle it has a new DPF fitted. (See Zetti DPF Tool article)