How to Prevent Diesel Particulate Filter Issues

Diesel particulate filters (DPFs) have been given a bad name after being the cause of costly failures for some vehicle owners, but are they really more trouble than they’re worth?

 

What are Diesel Particulate Filters?

These filters prevent harmful particles being released into the atmosphere by capturing and storing exhaust soot produced by diesel vehicles. The soot in the filter is then burned in a regeneration process. Since 2009, when the Euro 5 emissions standard was introduced, DPFs have been mandatory for all new cars with diesel engines.

 

What Makes Diesel Particulate Filters Fail?

Diesel particulate filters can become clogged by the soot that they are trying to trap, and if this is not cleared by regeneration, the filter may fail, leaving you with a hefty repair bill. DPF blockage is the most common cause of DPF problems and can be caused by a lack of servicing, performance modifications and regular short journeys at low speeds; this is why diesel cars are better suited to those who travel on the motorway often.

 

How to Look After a Diesel Particulate Filter

The reputation of diesel particulate filters has been unfairly tarnished. The truth is that the majority of failures are simply down to driver ignorance and can be avoided with proper maintenance. If your vehicle’s DPF becomes blocked, a warning light should appear on your dashboard to alert you to the issue, so you know when to take action. To burn the collected soot, a car’s exhaust must be given the chance to reach a high enough temperature to start the regeneration process.

Active Regeneration

Active regeneration occurs automatically when the soot level in the DPF reaches around 45%. Extra fuel will be injected to increase the exhaust temperature at lower speeds.

Passive Regeneration

Passive regeneration occurs when the vehicle achieves high speeds for a prolonged period. If the DPF warning light appears, try taking a motorway drive lasting more than 30 minutes to allow the exhaust to reach the temperature needed to burn off excess soot.

Forced Regeneration

If passive and active regeneration is unsuccessful, and the warning light does not disappear, some service centres can offer forced regeneration, which, as a far cheaper option than a replacement DPF, is definitely worthwhile.

 

Here at MotorServ UK, we can advise on all DPF issues, providing initial advice, treatment and replacement only where necessary.