Regeneration And Cleaning Of The Diesel Particulate Filter

Since 2007, diesel engine manufacturers started putting diesel particulate filters (DPF) in exhaust systems. These filters are wonderful for the environment, filtering out tiny soot particles from the exhaust before they can get into the atmosphere. However, if not properly maintained, they will require repairs that are quite expensive. Avoiding these costly repairs is a two-step process. The first process is regeneration, and the second step is cleaning it.


Regeneration of the DPF is accomplished when the accumulated soot is burned out of the filter. This can be done either passively or actively. Passive regeneration occurs when the vehicle is driven at high speeds, has a heavy load, or anything that causes the exhaust temperature to rise above 950 degrees F. It is not common for normal driving to allow for complete passive regeneration.

If passive regeneration is not taking care of all the soot built up in the filter, active regeneration is required. Once the filter has a specified accumulation of soot, the electronic control unit (ECU) in the engine will signal the fuel injectors to release additional fuel after combustion between cycles. This will cause an increase in the exhaust temperature so the particulates can be burnt off. It is important to read the vehicle's owner's manual to know how long you need to keep driving when active regeneration is occurring or the process will not be complete and you will end up with a clogged filter.


While regeneration will take care of the particulates in the exhaust, ash from the burning process accumulates in the filter. This requires cleaning. If you are mechanically inclined, you may be able to remove the filter from within the exhaust system yourself. You cannot clean the filter by banging it on anything; this will only break it. There are a number of additives available on the market that claim to clean the DPF, but it is best to take the piece to a professional shop to have it cleaned.

It may be tempting to remove the DPF and avoid the problems of ensuring complete regeneration and cleaning. However, removing it, or making it inoperable is illegal and will result in fines. In addition, even if you take it off and then have it put back on for inspections, you will need to adjust the ECU in the vehicle to keep it from reacting to the emissions and causing other parts to malfunction. It is much easier, and better for your vehicle, your wallet and the environment to keep up with what is going on with the DPF at all times. For more information about diesel filters, go to site.