DPF Maintenance, much like all preventative maintenance, is often something that is treated as an afterthought. When it is working as it should, the DPF is usually taken for granted and/or forgotten about; even though it is providing a vital service to ensure the emissions from your vehicle are at a legal level.

The moment a DPF stops doing what it should, and the MIL light comes on, it suddenly becomes a cause for concern and something that needs to be addressed as quickly as possible. With luck your vehicle won’t enter limp mode and leave you stranded, allowing you time to get to a garage or back to your workshop so the DPF can be fixed or replaced before even more damage can be done. But sometimes it is too late and, not only could you be stranded roadside, but also be burdened with a huge bill to replace the entire emissions system. Fortunately, preventative maintenance can avoid such issues and allow you to operate your vehicle without fear of DPF / emissions system failure.


How do I look after my DPF?

NOxBUSTER City upgrades buses up to Euro 6

Step 1: Burning off soot by driving

The first and most cost-effective step is to operate the vehicle for a reasonable time at a reasonable speed to allow the exhaust to heat up and burn off the soot and other matter that has accumulated. A twenty-minute run on an A-road at 50-60mph (where permitted!) might normally be a part of your day that you take for granted (or even detest at times!) but it does a lot of good for your exhaust. DPF’s are designed to burn off soot during operation in order to prevent them from blocking but this can only happen once the filter is hot enough, approx. 600°c.

Conversely, if your vehicle is never able to reach these speeds regularly and/or you spend a lot of time driving in an urban environment, this process cannot happen. This leads to high levels of ash accumulating in the DPF and eventually blocking it. So ensure you have a non-interrupted 20+minute drive factored into your weekly or monthly routine (depending on the workload of your vehicle) to reduce the risk of DPF blockage.

FSX cleaning - SCR Silencer Catalyst Cleaning

Step 2: Clean your DPF professionally

While step 1 can keep your DPF relatively clean it is still worth getting it cleaned professionally once a year. Most soot will burn off once the exhaust is hot, but remnants will exist and eventually build up. This, on top of an accumulation of ash and other matter, will lead to a reduction in efficiency and a decreased flow through the filter.

DPF’s have hundreds of cells each of which channel the exhaust gases from the engine through the filter. Each of these are like the chimney on a house and, although they may not block, they can become dirty and inefficient. In most cases a thorough clean with a flash cleaning machine or an FSX cleaning machine will bring the flow rate of the unit back to 98-99% of its original value. Excalibre Technologies utilise both machines and have the facility to heat DPF’s up to over 300°c to burn off any stubborn ash that cleaning alone may not remove.

ULEZ compliant exhaust fitting

A Routemaster bus is retrofitted with a new ULEZ compliant exhaust at Clapton Bus Garage. 14/2/2019

Step 3: Whole body servicing

Regular maintenance of the rest your vehicle is essential. Most permanent damage to a DPF filter is caused by negligence or running the vehicle for a prolonged period with a pre-existing fault. One issue we often get at Excalibre Technologies is DPFs that have exothermed. This is where ash gathers in the DPF while the exhaust has been running at a low temperature and is then ignited once the silencer becomes hot, thus melting the cells in the substrate irreversibly blocking them. Problems also frequently occur when turbo and engine failures fill the exhaust with oil – this can deactivate catalysts and make the units almost impossible to clean.

Again, regular servicing, paying particular attention to faults and the vehicles maintenance plan can help to avoid these engine issues and therefore protect your DPF.

Excalibre Technologies logo

About Excalibre Technologies

Founded in 2007 (a year before the introduction of LEZ), Excalibre Technologies was born with the intention of offering high quality commercial vehicle emission control products and services at a competitive price with customer service at the heart of our operation. Since then Excalibre has grown to become a leading supplier of retrofit solutions and DPF cleaning services in the UK.

We work with several national organisations to help achieve their ecological targets of lowering emissions and ensuring their vehicles are maintained to a high standard using internationally recognised practises and equipment supported by OEMs. We can also supply most aftermarket silencers and catalytic converters.

If we can help you with your emission control requirements, please contact Excaibre Technologies on 01594 887414 or sales@excalibretech.com.

Follow us on FacebookTwitterInstagram and LinkedIn  to stay up-to-date with the latest news about Low emission zones (LEZ) clean air zones (CAZ), ultra low emission zones (ULEZ), Bear funding (the Scottish Bus Emissions Abatement Retrofit programme), refrofit solutions, retrofit funding and DPF cleaning.