Ministers are facing urgent calls for reform with fears that the current MOT is failing to identify many cases of DPF removal because it only includes a ‘visual inspection’ of the hardware, which can be welded back together.
1,188 vehicles have been caught without a DPF since 2014 when ministers introduced a visual check into the MOT, according to figures obtained from the Department for Transport (DfT) by the Guardian.
The DfT has now commissioned research to better detect DPF removal by measuring exhaust fumes and any findings could be implemented as part of changes to the Roadworthiness Directive, which is scheduled to be introduced in 2017-18.
Dave Garratt, chief executive at the Garage Equipment Association (GEA), said: “[DPF removal] has been going on for a long time and it is probably getting progressively worse.
“The biggest hole in the MOT is that they don’t really check it.
“[Visual inspection] does not actually tell you if there is a core in the canister.”
Almost 29,000 deaths are attributed to particle pollution each year in the UK, according to a report published by DEFRA in September.
Simon Birkett, director of Clean Air in London (CAL), said: “CAL estimates that tens of thousands and more likely hundreds of thousands of diesel vehicles have been tampered with in this way.
“As more and more vehicles come out of warranty and parts wear out, this problem will grow.”
DPF deletion services
A separate report, published on GW in October, found that at least 1,000 garages are offering DPF removal for as little as £250 but Paul Clark, managing director at European Exhaust and Catalyst, told GW that “DPF removal is a risky business”.
He said: “Not only will it invalidate car insurance and potentially fall under the veil of tax evasion, due to low emissions based road fund licensing, but it can damage the performance of the vehicle as well.
“At EEC we have heard many horror stories about vehicles in limp mode, engine management lights on and poor running performance and actively warn people of these dangers through our technical seminars.”
Clark explained that problematic injectors, throttle bodies, EGR valves, MAP sensors, MAF sensor and IAT sensors can all have a negative impact on the filter’s operation.
“Look at all the options available to you in the aftermarket before considering a removal, as just removing the DPF will not necessarily be the answer,” he adds.
Legal options for the motorist
Many motorists are being “cheated” with DPF deletion services, according to Klarius, who warn that often “the original fault which caused the failure of the DPF” will not have been remedied.
A Klarius spokesperson told GW: “There is a lack of technical knowledge concerning DPFs in the trade, compounded by misinformation shared amongst some mechanics.
“Research has shown the poor quality of some aftermarket DPFs with reduced filter components inside.”
“Klarius is the only manufacturer who offers the premium replacement for the price of a standard aftermarket DPF, incorporating OE sized filters which guarantee the original performance and efficiency of the vehicle is retained or even improved.”
Profitable for independents
Launched last year, an innovative new professional DPF cleaner offers garages a new alternative to DPF replacement.
Speaking to GW about the product, John Wright, garage essentials manager at GSF Car Parts questioned why the practice of DPF removal still exists now that cost-effective solutions are readily available for garages.
He said: “The cost of removing a DPF is likely to be more than it is to treat it with the new Vetech DPF professional cleaner.
“If you’re removing it anyway, it makes sense to treat it with this pour in product.”
Visual DPF checks became part of the MOT in February 2014 and law states that it is illegal to drive a vehicle in the UK without a DPF if it was originally designed with one.
Do you support calls for a DPF removal crackdown? How many cars have you failed during a test due to removal? Share your experiences and any concerns in the comments below.