There are a lot of different kinds of smoke and mirrors when it comes to diesel that is ‘DPF-fitted. A DPF is an exhaust filter that is fitted to most late-model diesel vehicles.

It is used for removing harmful gases including hydrocarbons from fuel or lubricants and sulfurates and water that stick to soot and form harmful particles. These harmful gases may be the result of a variety of contributing factors, including poor or incorrect servicing, low-quality fuel, or poor driving habits which result in poor combustion.

The DPF filter is designed to capture these particles and then be regenerated, or cleaned by high-temperature burning. Problems occur because the regeneration process fails or the filter gets clogged. I’ve seen diesel’s particulate filter described as an expensive and sophisticated component that needs to be replaced. This is, however, not my experience.

It is possible to avoid replacement If it is controlled, diagnosed, and properly maintained. A DPF fault in an engine’s computer does not necessarily mean that the DPF is blocked.

What are the symptoms of blocked DPF

There are several symptoms that could occur when your DPF becomes clogged and/or needs to be cleaned (not necessarily ready to be put on the scrap heap).

  • Surging/poor performance.
  • Excessive fuel consumption.
  • Smoking excessively blue, black, or white.
  • Display of engine and/or DPF emissions light.
  • It is difficult to start the engine.
  • The engine is running rough.
  • Failure to regenerate.

What are the definitions of regeneration?

The vehicle’s computer-embedded algorithms perform periodic regenerations (burns), which raise the temperature of the exhaust in order to ‘burn away’ any soot or particles. A component that is not working correctly can cause an increase in regenerations, or stop them completely until the issue is fixed. Regenerations result in blowing excessive black smoke out of the exhaust. This isn’t harmful. If smoke is constantly blowing is it a sign that an underlying problem requires immediate attention.

What can you do to minimize the risk of DPF failure/blockage?

  • Make sure that the mechanic you hire is experienced and knowledgeable in diesel.
  • Avoid Incorrect oil and services that are not present.
  • Avoid driving with a defect in your car (dash warning light).
  • Avoid poor-quality diesel fuel. Modify your car with care. I deal with DPF driving behaviors – decrease idling (increase the rpm at a lower speed than load) and then lowering a gear, especially in crawling.
  • Talk to your mechanic about any changes to your vehicle such as louder whistles, hissing sounds, or a jerking sensation while driving. These unusual changes in driveability could cause your DPF not to regenerate.
  • Avoid using ‘on vehicle intake/induction cleans’ even if your mechanic suggests these. They could damage DPF’s as well as other major components.
  • DPF faults can be caused by malfunctioning components, but they don’t always require replacement.
  • A maintained DPF can last for 200,000 + km before removal to ensure proper cleaning or replacement.

What does it cost to clean or replace the DPF

First, a warning: DPF repair MUST be performed by a skilled mechanic with the right tools to reset and replace DPF. After the initial fault is confirmed after which the DPF should either be cleaned or removed with a DPF cleaning service. The top DPF cleaning firms should have a minimum of five years of success in cleaning. They can also tell whether the DPF is actually damaged in-house.

A mechanic can look at the DPF of the vehicle to determine if it is blocked. They cannot determine whether the DPF is melting or has collapsed inside, causing the blockage. A passenger vehicle’s average cost of cleaning is approximately $600. There’s a wide range of vehicles fitted with DPF’s. Manufacturers frequently alter their designs, which makes it difficult to determine which DPF brand is best for a particular vehicle. Since the DPF is the most tightly regulated component of motor vehicles, it does not reveal who the DPF manufacturer might be.