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DPF cleaning and repair
A diesel particulate filter traps soot from the exhaust and burns it off automatically when the exhaust gets hot enough, which is called regeneration.
What dpf cleaning means
Cars used mainly for short, cold journeys may never get hot enough, and the filter gradually blocks. A garage can force a regeneration, clean the filter on or off the car, or replace it.
What the job covers
- Forced and static DPF regeneration
- On-car and off-car DPF cleaning
- Differential pressure sensor faults
- EGR valve cleaning and replacement
- DPF replacement where cleaning will not recover it
When you might need it
- A DPF warning light, often with a message about driving at speed to clear it.
- The car goes into reduced power mode, or the engine sounds different and fuel use rises.
- Mostly short journeys, especially in winter, with the engine rarely reaching full temperature.
What it costs, and what changes the price
Typically £250 to £1,500.
- A forced regeneration costs least and works when the filter is not too far gone.
- Off-car cleaning costs more but recovers filters that a forced regeneration will not.
- A replacement filter is the most expensive option by a wide margin, which is why catching it early is worth doing.
How long it takes
A forced regeneration takes about an hour. Removing and cleaning the filter is usually half a day.
What the MOT data shows
Out of 42,728,066 MOT tests in 2025, these are the parts covered by this job that testers recorded as faults.
| Part | Recorded in 2025 |
|---|---|
| Catalyst emissions | 436,271 |
Common questions
Can I clear it myself by driving?
Sometimes. A steady run at motorway speed for twenty minutes or so gives the exhaust a chance to get hot enough, and that is often all a partly loaded filter needs.
Is removing the DPF an option?
No. Removing it is an MOT failure and it is against the law to use a vehicle on the road with it taken out.
Why does mine block when my neighbour's does not?
Journey length, mostly. A car used for a few miles at a time never gets the exhaust hot enough to burn the soot off.