Diesel-specific filters, also known as DPFs have become the solution of choice for a variety of manufacturers to eliminate soot and ash after burning diesel. In essence, they’re an exhaust filter that collects soot and stores it for processing during a dpf burn.
Performance is the main focus of our lives and we’re aware that any restriction is going to affect the performance of an engine. So what can we do about the DPF? What is it and how to look after it?
The DPF can be eliminated from the exhaust and the software. This is a simple solution to every problem caused by a DPF. I’m not going to discuss details of the legalities involved in removing any emission-related device. I’m simply saying this is the best solution.
One advantage of DPF is reducing soot getting into the air. It is, according to some, a positive benefit for the environment. It’s a vague phrase at best. It is necessary that a DPF regenerate or burn off soot frequently. The method to achieve this is to make the DPF hot enough to burn off the soot so that it is able to pass through the filter. One method to accomplish this is when the ECU injects fuel to generate temperature in the filter for it to burn off. This obviously requires more fuel (not eco-friendly) And a lot of this fuel is absorbed into the sump of the engine, reducing the engine oil. This could result in additional oil and filters being changed.
Similar to the catalytic converters were introduced and lead had to be removed from the fuel since it could cause a problem for the converter. Vehicles with DPFs require special oils that are low in sulfate ash and sulfur, phosphorus, and sulfur (low levels of saps). Incorrect oil will block the DPF and hinder its regeneration making it necessary to replace DPF. One negative aspect of DPF is that it is expensive to replace.
Some say that the requirement for oil in the DPF results in internal engine wear rates higher than if regular oil was employed. We’ll have to debate that one day.
The most common issue we encounter in DPFs is when a boost leak is observed. A boost leak will cause more soot to build up in the exhaust and block the DPF very quickly. After the leak has been repaired, then a DPF clean is likely to be necessary. You can conduct a DPF clean with the DPF still in the vehicle. After the DPF clean has been completed it is possible to perform a regen. Whenever it is necessary to carry out a forced regen, an oil change for the engine will be required following the regen. Do you remember to do this before you inject fuel to get the DPF sufficiently hot to allow it to be able to regulate it? This fuel added will make the engine oil less effective.
In the most extreme instances, forced regens will not be possible because of the volume of the soot load. The next step in the process is an on-car cleaning. Our car cleaner involves two steps. The cleaner is injected into the DPF and processes the soot over a given amount of time. The cleaner then is removed from the system which leaves the DPF ready for a forced regen. The car-specific cleaning equipment is even less common for a workshop to have. We can also help with the car DPF cleaning.
This is an introduction to the DPF and some of the advantages and disadvantages associated with its usage.