What is a DPF Filter? (Diesel Particulate Filter)
Following changes in emission laws and regulations from 2009 most diesel engines are fitted with a diesel particulate filter (DPF). Its primary function is to capture and store exhaust soot (particulate matter) to reduce emissions from the car.
Over time, the accumulated soot needs to be burned off to regenerate the DPF, preventing it from becoming clogged. This filter is required to be cleaned through self-regeneration whilst driving your vehicle to ensure the filter performs correctly and prevent future repair costs in relation to the DPF failing.
(Please consult your vehicle handbook either manually or online, so you may correctly identify the DPF light which will show on your dashboard as different manufacturers vary).
When the light shows it does not mean there is a fault on the vehicle. It means the vehicle needs help to carry out DPF regeneration. The procedure involves the vehicle being driven in a certain way to help increase the exhaust temperature.
Tips for Maintaining Your DPF Filter
1.Regular Long Drives: Short trips can cause the DPF to clog up as it doesn’t get hot enough to burn off the soot. Taking your car for a longer drive periodically can help the filter regenerate. (A period of 20/25 mins should be enough)
2.Use the Right Oil & Service on Time:
Ensure you use low-ash engine oils as specified in your vehicle’s manual to prevent additional buildup in the filter. Get your oil changed regularly – we would recommend every 8-10k miles – most cars will give you a dashboard countdown.
3.Follow Manufacturer’s Guidelines:
Consult your vehicle’s manual for specific instructions regarding DPF regeneration and fuel requirements.
4.Monitor Dashboard Warnings:
If you see a DPF warning light, don’t ignore it. Act promptly to avoid costly repairs.
5.Professional Cleaning:
Occasionally, it might be necessary to have your DPF filter cleaned by a professional to remove stubborn soot buildup.
6.Maintain Fuel Levels:
If there isn’t enough fuel in the tank, the regeneration process may be interrupted or not initiated at all. An interrupted regen can cause the DPF to become clogged over time, leading to reduced performance and potential engine damage.
7.Ensuring Proper Function:
Certain systems within the car rely on adequate fuel levels to function correctly during regen. For instance, the engine control unit (ECU) monitors the fuel level and other parameters to determine if conditions are optimal for regeneration.
BEWARE: If the cleaning process is repeatedly interrupted:
Cleaning takes the shortest amount of time at high engine speeds and the DPF light will turn off as soon as self-cleaning is complete. MONITOR your car’s behaviour – if there an increase in fuel consumption or you become aware of multiple failed regenerations (indicated via a light on the dashboard or through hearing the cars fan continuing to run for some time after the engine has been shut down) do not delay in contacting your mechanic as with failed regenerations fuel will pass into the sump, and you’ll notice a higher oil level when you check it. (This is one reason to check your oil level regularly.) For short journeys, please check more often and, if you find your oil level has increased, change the oil sooner.
FINALLY!
Repeated short journeys without factored in longer journeys now and then and failure to take notice of any lights illuminated on the dashboard or to check oil levels regularly can cause the DPF filter to block up, especially if the above regeneration tips and processes are not followed. If this happens, it may not be covered under any warranty supplied with the vehicle.
KEY TAKE AWAYS
Keep car fueled (never let below quarter full)
Be Aware of the regeneration process
Use good quality fuel, cheaper alternatives WILL CAUSE long term damage
DO NOT IGNORE any lights on your dashboard! Get them diagnosed asap – they may be minor, or they may need immediate attention which could save your pocket in the long term.
