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DPF (Diesel Particulate Filter) Cleaning
All You Need to Know About DPFs (Diesel Particulate Filters)
DPF filters are crucial in reducing polluting exhaust gases from diesel engines.
Maintaining and cleaning your DPF can significantly enhance your vehicle's performance and longevity.
This guide provides all the information you need about DPFs, focusing on DPF cleaning.
What is a DPF Filter?
Unlike petrol engines, diesel engines utilize a compression-ignition combustion process that produces a sooty by-product.
If emitted as untreated exhaust fumes, invisible particles within this soot can pose significant health and environmental risks. A diesel particulate filter (DPF) traps this soot and harmful particles, preventing them from being released into the atmosphere as the characteristic smoky black exhaust fumes seen in older diesel vehicles.
To reduce CO2 emissions from vehicles in Europe, the European Union introduced Euro 5 exhaust emissions legislation in 2009. This regulation mandated the inclusion of DPFs in all new diesel cars manufactured in the EU.
It is illegal to remove a DPF, and its presence is verified during your vehicle's MOT test. If caught driving without a DPF (where one was initially installed), the penalties can be severe—up to £1,000 for cars and £2,500 for light goods vehicles.
How do DPFs Work?
The interior of a Diesel Particulate Filter (DPF) typically consists of a highly porous silicon carbide honeycomb.
As unfiltered diesel exhaust fumes pass through the DPF channels, the porous walls of this catalytic honeycomb trap solid harmful particles, allowing the filtered gaseous components to escape as vapour.
While this process effectively prevents most harmful particles from being released into the atmosphere, the trapped soot forms a 'cake' layer inside the filter.
An excessive buildup of this layer can lead to blockages, which can fill the DPF and potentially cause breakdowns.
DPF Warning Light Explained
The DPF warning light on your dashboard indicates that your filter is becoming clogged and requires regeneration or cleaning.
Common causes include frequent short trips, which do not allow the DPF to reach the temperature needed for passive regeneration.
If this light comes on, addressing the issue promptly is crucial to prevent further damage.
Passive DPF Regeneration Process
Passive DPF regeneration occurs naturally when the exhaust temperature is high enough, typically during prolonged highway driving at constant speed.
This process burns off accumulated soot without driver intervention.
Regular long drives facilitate passive regeneration, thus contributing to effective DPF cleaning and maintenance.
DPF Cleaning
Regular DPF cleaning is vital for keeping your vehicle running efficiently. There are several methods for DPF cleaning:
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Manual Cleaning involves removing the DPF and cleaning it with specialized tools and solvents.
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Chemical Cleaning: Utilizes a DPF cleaning additive to assist in soot burn-off during regeneration cycles.
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Professional Services: Some garages offer DPF cleaning services using high-pressure air or thermal cleaning processes.
Consistent DPF cleaning ensures better performance, lower emissions, and avoids costly repairs.
Exhaust After-Treatment
Certain vehicles utilize a fuel treatment called EOLYS, which is injected into the fuel tank to lower the temperature required for regeneration.
This fluid reservoir needs periodic refilling or replacement.
Additionally, many diesel vehicles use AdBlue™, a fluid that must be kept topped up while not directly affecting the DPF to avoid other issues.
Is it Illegal to Remove a DPF?
Yes, it is illegal to remove a DPF from your vehicle.
Removing the filter can lead to severe legal repercussions, including fines and penalties.
Moreover, it significantly increases the amount of harmful emissions released into the environment, contributing to air pollution and health risks.
Active DPF Regeneration Process
The vehicle's onboard computer initiates active DPF regeneration when the filter needs cleaning, and passive regeneration has not occurred.
During active regeneration, extra fuel is injected into the exhaust system to raise the temperature and burn off the soot.
Drivers may notice a slight increase in fuel consumption and exhaust heat during this process.
Forced Regeneration
Forced regeneration is a manual process conducted by a professional when neither passive nor active regeneration has successfully cleaned the DPF.
This service uses specialized equipment at a service centre and involves raising the exhaust temperature to burn off excess soot.
While highly effective, forced regeneration should only be done when
necessary.
Summary
Maintaining a clean DPF is essential for optimal vehicle performance and compliance with emission standards.
Regular DPF cleaning, following the regeneration process, can help keep your filter in top condition.
If you experience persistent DPF issues, contact Motorcare promptly to avoid extensive damage and ensure your vehicle remains environmentally friendly.
What Do I Do if Neither Active nor Passive DPF Regeneration Work?
If neither active nor passive regenerations are effective, call Motorcare for a consultation.
Motorcare can perform diagnostic tests to determine the cause of the issue and may recommend forced regeneration or DPF replacement if necessary.
Ignoring this problem can lead to more severe engine damage and higher repair costs.
Should I Call a Breakdown Service if the DPF Light is Glowing?
If your DPF warning light is glowing and you are unsure what to do, it is wise to contact your breakdown service provider.
They can provide roadside assistance and diagnostics to determine whether your DPF requires immediate attention.
They can also offer advice on preventive measures to avoid future issues.