The DPF, or Diesel Particulate Filter, is one of the main reasons modern diesel engines are experiencing reliability issues. Designed to reduce harmful emissions and limit the release of particulate matter into the atmosphere, the DPF has become a necessary component of modern diesel vehicles.

The problem is that the DPF can also create complications. In simple terms, it restricts exhaust flow and relies on regular regeneration cycles to burn off accumulated soot. When those regeneration cycles don’t occur properly, the filter can become clogged, leading to a range of issues.

Modern engines must comply with increasingly strict emissions regulations, forcing manufacturers to develop new technologies to meet those standards. Some companies, most notably Volkswagen during the Dieselgate scandal, attempted to circumvent the rules. Others have sought legitimate engineering solutions.

However, those real-world solutions can bring their own challenges. Excessive soot build-up, DPF blockages, increased fuel consumption, warning lights, reduced performance and engines entering limp mode are all common complaints among diesel owners.

The simplest way to avoid these problems is to ensure a diesel vehicle is driven regularly on longer journeys, allowing the DPF to reach the temperatures required for regeneration. Frequent short trips can prevent this process from occurring and increase the risk of blockages.

My view is even simpler: don’t buy a diesel car unless your driving habits genuinely suit one. Modern petrol engines have become far more efficient and can deliver impressive fuel economy, sometimes approaching diesel-like range. Alternatively, if your circumstances allow, an electric vehicle removes the DPF issue altogether.