In-Depth Why does the DPF Filter get clogged with soot ?

Discussion in 'Technical Articles' started by Ichiban, Friday 20th Dec, 2013.

  1. Ichiban Founder Staff Team

    England CJ Leeds
    There are a few reasons why a DPF filter can become blocked, and to clear the misconception out there.

    Low quality fuel or problems with fuel injector’s i.e. Using Supermarkets fuel
    These can both cause poor running and also increase the level for the soot in the exhaust system which can clog the filter more quickly. It doesn’t help when majority of the fleet car managers and large corporation send emails to their staff to use supermarket fuels. A few small business and large companies have given their staff supermarket fuel cards to reduce the burden of increasing fuel prices, ultimately which does not help the DPF filter on the car. If you use your own car please stick to the major oil companies for your diesel.

    Driving Short Distance or stop start driving.

    If you are only driving short distances or are on a journey where you are stopping and starting frequently your diesel particulate filter will not be able to reach its optimum temperature to regenerate itself. If the warning comes on the dashboard then don’t switch the engine off, let the natural DPF regeneration place. If you do stop the engine it you will need to go into a dealer for a forced regeneration. Have a look at the leaflet given to Honda Diesel customers, see below.

    Sticking ERG Valve

    Your exhaust gas recirculation valve (EGR) helps control the recirculation of your exhaust gas back into your engine, this helps lower fuel consumption and also helps your engine to run cooler. It also makes the engine very efficient by reducing pumping losses. If the valve is stuck in either the open or closed position it will affect the mixture of fuel and air causing your vehicle to run rich or lean. A rich mixture will affect your DPF significantly and block it much faster than an engine that is running at its optimum efficiency. The people who are forced to believe an EGR removal has numerous advantages make sure you first understand how the EGR works. Please don’t be lead into believing a complete blockage of exhaust gasses is better as it cleaner for the engine! Make sure you understand how the file uploader has set the AFR (Air Fuel Ratio). If they cannot answer this simple question or provide you with an AFR reading through the engine rev range or engine loading then walk away from the deal. The will also try to hide behind the “its trade secret and cannot tell you our tuning AFR table”. A tuner who educated and enthusiastic turner will explain the pitfalls of an EGR delete; just make sure you are up to speed on the terminology to make the informed decision.

    Engine oil
    . Make sure you use DPF compliant engine oil every time you change the engine oil or topping up. Also have a look at these threads for further information