Are you worried that your car's diesel particulate filter is becoming blocked?
Read on and find out what causes your DPF to become blocked, and what you can do about it.
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Why Is My DPF Blocked?
If you drive a diesel car that was built after 2009, then it will have a diesel particulate filter (DPF).
This clever car part works to trap the soot produced by your car when diesel is burned off.
This helps to reduce the harmful emissions that your car produces, by preventing them from entering the atmosphere.
Unfortunately, as this soot level builds up over time, your DPF will become blocked.
Your DPF may be blocked if you notice any of these warning signs:
- A loss of performance
- A loss of power
- DPF regeneration cycle failing or not finishing
- Rising oil level
- Your car is using more fuel
- Heavy smoke
- You smell diesel
If you notice any of these problems, then your car may be in need of a DPF clean - particularly if you haven't booked one in a while.
What Should I Do About My Car's Blocked DPF?
Your car needs to go through a process known as regeneration in order to burn off the soot that will build up over time.
Regeneration can be active or passive, but both types are an attempt to raise the temperature of your exhaust to target the soot.
Passive regeneration can be triggered by driving on the motorway for 15 minutes or more at a speed of at least 40mph.
This will raise the exhaust temperature and burn off some of the soot in the filter.
A layer of ash will remain even after regeneration, and this in itself can cause problems for your DPF as it hardens over time.
Your car’s DPF warning light will light up to let you know once your DPF is almost 70% full of soot, at which point your car’s performance will be limited.
To ensure that this level doesn't increase - your DPF will need replacing once you hit 90%.
Will a Blocked DPF Damage My Engine?
A blocked DPF can cause severe damage to your engine.
This is because your engine is having to work a lot harder to vent the exhaust fumes that your blocked DPF is failing to.
This can lead to weakened acceleration, increased fuel consumption, and the risk of leaks.
DPF cleaning can improve your car’s performance, by taking this pressure off of the engine.
If you neglect this filter for long enough, you could see other issues, like melted filters, low vehicle power, and your DPF itself may even crack.
Whilst you can buy DPF cleaner designed to flush out the insides of your car when regeneration cannot be completed, this won't help to unblock a significantly blocked DPF.
A professional DPF clean is the best option if you really want to notice a difference in the quality of your car's diesel particulate filter.
Can I Remove a Blocked DPF Myself?
It is illegal to drive without a DPF in the UK - your car will likely fail its MOT - or to remove a DPF if it was originally fitted as standard to the vehicle.
However, it is not illegal for this to be replaced or repaired if faulty.
Anyone with an extensive understanding of the mechanics can change a DPF.
If you do not have the necessary knowledge and technical skills at your disposal, we would strongly advise that you opt for this DPF repair or replacement to be carried out by a fully-qualified mechanic.
When a DPF is removed and replaced, the soot values have to be reset in the ECU - otherwise known as the electronic control unit.
This is yet another reason to have the job performed by a professional garage, as they will be able to reset the dashboard warning light for you.
How Long Does It Take to Unblock a DPF?
When you take your car to a professional garage for a DPF clean, the whole process can take up to 2 hours to complete.
An expert mechanic can put your DPF through a process called forced regeneration.
During this process, a mechanic will be able to burn away the soot particles in your diesel particulate filter.
How Much Does a DPF Cleaning Service Cost?
It is definitely worth booking a DPF clean every 6 to 9 months to keep your DPF working well.
When you book in for a DPF cleaning service through BookMyGarage, this can cost you as little as £99.
This includes a full inspection, diagnosis and flush, all performed by highly-qualified mechanics.
By booking a DPF clean, you can get your car in the best shape possible in time for its next MOT.
Keep fuel costs to a minimum and expensive DPF replacement costs at bay - book in for a DPF cleaning service today!
