DPF & EGR solutions

We are frequently asked about Diesel Particulate filter (DPF) problems and Exhaust Gas Recirculation (EGR) valve problems. We some advice.

WARNING! Both the DPF and EGR devices are fitted to your vehicle to reduce poisonous emissions and the law requires that they are not removed.


The problem is that these devices can fail. Both can get blocked up, particularly if the vehicle is not regularly driven at cruising speeds or above. The first sign of this is a warning light illuminated on the dashboard.


Professional cleaning of your Diesel Particulate Filter (DPF)!  There are a number of professional DPF cleaning providers.  One you could try is GAP-TURBOS who provide a 5-stage cleaning process and also provide a 12 month warranty on the work carried out.  You can contact them using the link below below.


Be warned!  some companies will remove the core from a blocked DPF and provide a remap to program out all DPF functions from the ECU. We always advise customers against this because it is illegal to use your vehicle on the road if the DPF has been removed.  New stricter MOT rules come into force in May 2018 and include much more stringent testing of the DPF.  If the DPF is suspected of being removed or tampered with, the vehicle will fail.  Also, the vehicle will fail if any visible smoke is emitted.

The Right Engine Oil…

You should always use ‘low SAPS oil for your diesel engine if you have a DPF. This type of oil reduces the amount of ash which builds up in the DPF. Trying to save money by using cheaper oil can cost you dearly in the long run. And of course make sure you use the correct grade of oil. Check your manual.

So how can you keep your DPF clean and trouble free?

Here are our 4 top tips…

DPF regenerations can only happen when road speed, engine RPM and engine temperature are above a certain minimum. Engine up to normal temperature, 2000 – 3000 RPM for at least 20 miles. Without these conditions, DPF regeneration will not take place. If you do a lot of slow driving, try and mix in some faster and less congested roads to maximise the chance of a regeneration. Some models need the fuel level at least quarter full.
Check your owner’s manual or ask the dealer how fast you need to drive, for how long and at what RPM to allow a regeneration cycle to complete.

Try to use the oil recommended by the manufacturer. Always check what grade of oil is needed, (e.g. SAE 5W50, etc) and you should specifically use low SAPS oil which is low in Sulphated Ash. This is a by-product of diesel combustion can block the DPF.

The EGR valve is important for the correct operation of the DPF. They can become stuck and this can lead to problems with the DPF. Check it’s clean and opening and closing freely.

OK, you’ve got the car you’ve got but when you next change it, consider if you tend to do lots of short journeys or spend a lot of time on stop start driving. A diesel car might not be the best choice for you. If you’re concerned about getting good MPG then some of the modern direct injection petrol engines have drastically closed the fuel economy gap between petrol and diesel engines.

What our clients have to say

Nissan X-Trail

"Hi Jeremy, just thought I would write to say how pleased we are with the remap of our x-trail. We had the remap done for better performance when towing and it’s done the job brilliantly. Towed the caravan today and on the hills, where earlier we would have had to change down gears to get enough power to climb up. It sailed up in 6th and still wanted to accelerate. Also, we noticed a difference in economy. Before the remap, the miles to empty would drop dramatically but we gained some miles today. There is also a noticeable difference without the van on the back. Thanks for a great job and will be recommending you to others." - Beckie, Willenhall

Mini Cooper S

"Thanks for sorting the mini out for me. Highly recommend Halesowen Engine Remapping to anyone. Great service, especially coming out to my house. Much better for me. Thanks again." - Darren, Birmingham

Mercedes 5 tonne Sprinter

"This remap has made such a difference! Brilliant service. Very smooth and feels like I'm driving an empty van. Superb result!" - Andy, Enfleet

Jaguar XF-R

"Many thanks for your work on Friday. I am delighted to say that power delivery is smoother and engine note on acceleration has a nicer "growl" to it. In addition, on the cruise home, I set the cruise control to the same speed that I came up at and got just under 2 mpg more! I will sing your praises to others." - Martin, Cardiff

Range Rover Evoque

"The remap carried out via Halesowen Engine Remap has totally transformed my Range Rover Evoque Si4 Dynamic Lux. When I first purchased the car, it had good power, but I always felt I could do with more. But wow! What a difference you have made to my car. It now accelerates like a scolded cat. It is brilliant around town, fantastic on country lanes and fabulous on the motorway. It is also more relaxed due to the added power. Unquestionably a great investment. You have made an excellent car into a truly fabulous car. Can't quite believe it. Many thanks." - Nick, Staffordshire

Subaru STI

"Had my Subaru done on Friday. Great result, good job. Would recommend to everyone. Thanks." - John, Kidderminster