What is a DPF?

DPF stands for Diesel Particulate Filter. It was introduced as part of emissions regulations to reduce pollution by trapping soot (particulate matter) produced by diesel engines. As the name suggests, it’s a filter located in the exhaust system that captures these particles before they leave the tailpipe.

How does a DPF work?

Over time, the filter fills with soot. To prevent it clogging, the car performs regeneration cycles to burn the soot away by raising exhaust gas temperatures.

• Active regeneration: the ECU deliberately increases exhaust temperature to burn soot, typically intended to happen during higher speed driving.

• Passive regeneration: found on many newer systems, where the DPF can regenerate more easily at lower loads and more varied driving conditions.

Why do DPF problems happen?

DPF systems rely on several sensors and conditions to trigger and control regenerations. If something in the system fails, regenerations may not occur correctly, soot builds up, and the DPF can become restricted.

A clogged DPF creates exhaust backpressure, similar to trying to blow through a straw with your finger over the end. That backpressure reduces performance and, in severe cases, can increase stress on components like the turbocharger. Manufacturers account for this risk by using safety strategies and limp modes, and in many cases a blocked DPF is a symptom of another underlying fault.

What does the DPF solution do?

A DPF solution disables DPF functions in the ECU, stops regeneration cycles, and removes related DPF faults.

Important: If a DPF solution is applied, the DPF must be gutted or replaced with a straight through section. Failing to carry out the required mechanical modifications can lead to serious damage, including catastrophic failure.