3 Signs Your DPF Needs Replacing

If you’re a diesel driver, chances are that at some point, you will run into problems with your DPF. Essentially functioning as your car’s soot filter, the DPF filters out the soot and diesel residue from your exhaust fumes. This is not a glamorous task, and after a while the filter will let you know that it needs to be cleaned out. This is how a DPF filter should work, but when it comes to cars, how things should be isn’t always how they are. 

Just like the car itself, a diesel particulate filter will get too old and no longer be able to function practically. Many drivers are content with keeping the same filter for years on end and keeping it ticking with a semi regular cleaning service. But there comes a time in every driver’s life when he has to replace their filter. Here are the three major signs that your DPF filter needs replacing.

Your DPF is Regenerating Itself Too Often

Most DPF filters have a natural method of cleaning themselves; active regeneration or passive regeneration. DPF regeneration is where the engine reaches a high enough temperature to burn away all the excess diesel residue. This can happen either naturally, usually during long durations of fast driving (passive regeneration), or when your engine decides that the DPF needs clearing and initiates this process itself (active regeneration). 

Active regeneration is written into the engine control units of most modern diesel cars, and usually creates excess fan noise and a pungent smell when it is in process. If your car is undergoing DPF regeneration too often, this could mean that the process is not working due to severe blockage. This will likely mean that your filter is too blocked to clean effectively, and will need replacing. 

The Filter Fills Up Too Quickly

Most DPF blockages can be cleaned with a thorough service, either through flash cleaning or chemical cleaning. This is a fantastic way to keep your DPF in good shape, and we recommend that you take your filter for semi regular cleaning to avoid gathering enough diesel soot and residue to build up, ideally before the warning light appears on your dashboard. If you feel as if your DPF filter is filling up too quickly after cleaning, it could be a sign that the mesh inside the filter has sustained damage or even malformed due to the heat of a blockage. This is a tell tale sign that your DPF is on its last legs. 

Your Driving Habits Make No Difference

Your driving habits should directly affect the behaviour of your DPF. There’s that word again. Should. As a general rule, when diesel cars are used primarily for long distance driving, the DPF filter has a much better chance of regenerating itself. This is due to the heat that the filter is exposed to when driving at high speeds for long amounts of time, which allows the soot to burn away naturally.

On the other hand, when diesel cars are used primarily for stop-start urban city driving, the filter cannot reach a high enough temperature to burn away the soot. Because of this, we recommend that diesel drivers who mainly drive in the city take their car for a long motorway drive semi-regularly to allow the soot in the filter to burn away. If you have tried this to no result, your DPF either needs cleaning or replacing, depending on the amount of diesel particulate matter that has built up in the filter mesh. 

Get in Touch

If you are still unsure whether your DPF needs replacing, let the team at DPF Cleaning Express take a look and we will recommend the best course of action for you. We stock a wide range of DPF filters that have been refurbished to factory condition. Browse our range of filters today, or get in touch with our team of technicians for more information on how we can help you.

DPF Filter | DPF Cleaning Express

DPF SQ1 | DPF Cleaning Express

Speak to an expert

Got concerns about your DPF? Whether it’s a repair, a replacement or just some advice about your filter, we can help. Get in touch with us using the form below, drop us an email or give us a call on 0114 3490923. We look forward to hearing from you.


0114 3490 923


Unit 3, The Gables
Holywell Road
Sheffield, South Yorkshire
S4 8AR