What to do about your diesel particulate filter during lockdown

The coronavirus lockdown is forcing people to drive their cars less, which could be a problem for owners of modern diesels

One of the inevitable effects of the UK being placed on lockdown due to the Coronavirus is that we’re all driving our cars less. This could present a problem for anyone with a modern diesel car.

For some years now, diesel particulate filters (DPFs) have been fitted to all diesel cars; it’s been part of the UK MoT test since 2013. In short, these devices capture and store soot produced by diesel engines in order to reduce emissions.

The catch with DPFs is that they only have a limited capacity and at some point the excess soot needs to be burned off. In order to do that, the car needs to be driven for around 15 to 20 minutes at 2,500rpm or higher. This process is known as DPF regeneration.

The Independent Garage Association (IGA) has warned that if people are only using their diesel cars for short journeys during the lockdown, though, their DPFs might not be able to regenerate. The organisation advises owners of modern diesel cars to avoid using them for trips of less than 10 to 15 miles in order to avoid clogging up the DPF.

When a DPF has built up too much soot and hasn’t been able to burn it off, a warning light will come on. If this happens, you should not use your car at all until you can get it looked at by a garage.

It may be possible for a mechanic to use specialist equipment to carry out a forced DPF regeneration, which is the ideal outcome. If this can’t be done, though, a whole new filter may be required, and this can cost up to £3,000.

If drivers ignore the warning light and carry on using their car with a full DPF, they risk blocking the DPF altogether, in which case the car will enter limp-home mode.

If drivers of diesel cars are in any doubt about the state of their DPF and are unsure what to do, the IGA advises them to call a garage and seek expert mechanical advice.

Find out everything you need to know to care for your car during the lockdown with our 2020 Car Care Special...

Recommended

DVSA backlog creates ‘grey market’ for driving tests
Driving test

DVSA backlog creates ‘grey market’ for driving tests

Learners say they’ve paid more than £200 to jump the queue and ditch their L-plates
1 Jun 2022
New car delivery times 2022: how long will you have to wait?
New car waiting times
Features

New car delivery times 2022: how long will you have to wait?

No one likes having to wait for their new car so we called key manufacturers for to get their latest UK lead times
11 Mar 2022
MINI stops production in Oxford until 18 March
MINI
MINI

MINI stops production in Oxford until 18 March

Semiconductor shortage and war in Ukraine cited as reasons for plant closure 
9 Mar 2022
Car dealer for the day: inside car sales and aftersales at a franchised showroom
Car dealer for a day - Cupra
Features

Car dealer for the day: inside car sales and aftersales at a franchised showroom

We play the part of car dealer and find out how dealerships have coped with Covid, the semiconductor shortage and new ways of doing business
28 Feb 2022

Most Popular

EU demands speed limiters on all new cars from next week: know the rules and how they work
speed limiters
News

EU demands speed limiters on all new cars from next week: know the rules and how they work

Car industry body calls for UK government to adopt the new measures, but we’ll probably get them anyway…
29 Jun 2022
New Nissan Ariya 2022 review
Nissan Ariya - front
Road tests

New Nissan Ariya 2022 review

Nissan is looking to reestablish its electric car credentials with the new Ariya and rivals should be worried
30 Jun 2022
Best car manufacturers 2022
Best car manufacturers header
News

Best car manufacturers 2022

We reveal the UK’s best car brands based on the feedback from car owners who took our 2022 Driver Power survey...
29 Jun 2022