Research commissioned by the Department for Transport (DfT) to better detect DPF removal has sparked debate among independent garages after it emerged that any findings could be implemented as part of the changes to the Roadworthiness Directive as early as next year.
The DfT has told GW: “Researchers have examined existing equipment used as part of the MOT smoke test and investigated the possibility of amending the procedure to determine if a DPF has been removed from a Euro five or six vehicle.
“Work is underway to ensure potential methods are robust enough to reliably determine a pass or fail.”
The news prompted a mixed reaction, with some praising the news in support of calls for cleaner air.
Commenting on GW, one reader said: “It’s about time something was done to put a stop to all these people removing the DPF.
“They are there for a reason.”
Flawed technology
However, not all welcome the DfT investigation, with many raising questions about the very effectiveness of the filters and highlighting their apparent flaws.
Tom Martin in Cumbria said that the filters seem to be “a false economy”.
“During a DPF regeneration, which burns the collected particles periodically, it releases a finer material which is absorbed into the blood stream.
“In highly congested areas such as Manchester and London this would logically lead to an increase in blood poisoning related deaths thereby merely reducing deaths in one area to another area,” he explained.
“Surely the DfT and government should be looking into this rather than railroading the utilisation of DPF systems with promises of reduced deaths, tax breaks and a cleaner, safer environment.”
Another reader, Martin said: “They still fail even with cars that have been serviced properly, and had the DPF fluid done as well and at the cost of £500-£1000 for a quality DPF, a lot of people can’t afford that sort of cost.
“We should return to old style catalytic converters for diesel again as they give lower emissions and can be cleaned and replaced a lot cheaper than your average DPF.”
Improved emissions
A number of technicians suggest that DPF deletion “allows the engine to breath,” helps the fumes exit faster and can actually improve emissions.
An anonymous reader wrote: “I have put this to the test with two cars same year, same engine, one with DPF, one without.
“Surprise surprise the one with no DPF had a lower emission reading, maybe the problem lies with the manufacturer’s mapping.”
Jake Dickinson questioned the future of diesels, saying: “As a mechanic, I’ll avoid a modern diesel and stick with petrol.
“DPF, EGR, common rail fuel systems, variable vane turbo, glow plugs, fuel additives, stop-start, not to mention dual mass flywheels.
“It’s a lot to go wrong and usually does.”
Many more GW readers have taken to Facebook to share their views on the topic.
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.
bill hardiman
DPF ??? I know lets store all the crap and then get on a motorway and blow it all out onto our food crops that line our m/ways
bill hardiman
DPF ??? I know lets store all the crap and then get on a motorway and blow it all out onto our food crops that line our m/ways
m cozens
as a mot test station why are we testing for the wrong gases on diesels we should test for nox
m cozens
as a mot test station why are we testing for the wrong gases on diesels we should test for nox
Motorman
Let’s face it these CAT/DPF diesel emissions systems are out there on the UK roads fitted to cars/vans/LCV’S and HGV’s in volume. New methods to check the presence of the exhaust filter and the performance of the system should form part of the annual MOT test and any other diagnostic procedure.
The problem which continues to exist is, the purchaser of a modern diesel vehicle more often than not at the time of purchase is not briefed/informed as to what implications exist if he has a specific driving style or short journey cycle (urban city use etc.)
Another problem which would improve things greatly is educating the garages/technicians explaining how these systems operate and how to diagnose and rectify faults in the correct order (I can tell you from experience a vast majority of the UK main dealers are at a loss when faced with DPF regeneration issues).
Motorman
Let’s face it these CAT/DPF diesel emissions systems are out there on the UK roads fitted to cars/vans/LCV’S and HGV’s in volume. New methods to check the presence of the exhaust filter and the performance of the system should form part of the annual MOT test and any other diagnostic procedure.
The problem which continues to exist is, the purchaser of a modern diesel vehicle more often than not at the time of purchase is not briefed/informed as to what implications exist if he has a specific driving style or short journey cycle (urban city use etc.)
Another problem which would improve things greatly is educating the garages/technicians explaining how these systems operate and how to diagnose and rectify faults in the correct order (I can tell you from experience a vast majority of the UK main dealers are at a loss when faced with DPF regeneration issues).
Peter Smith
If DPF filters have to be fitted and present for the vehicle to be used legally on the road then they should be guaranteed to last for the lifetime of the vehicle and replacement made at manufacturers cost and not the end users.
Steve
100pc agree. I am currently in my MOT station and bricking it waiting to see if they will fail because of no DPF. I had little option but have it removed from my 2008 Shogun. It is flawed technology! It’s like vacuuming your home and when the bag is full then dumping the contents on your carpet. Is there anyone out there who has not had problems due to their DPF?
Peter Smith
If DPF filters have to be fitted and present for the vehicle to be used legally on the road then they should be guaranteed to last for the lifetime of the vehicle and replacement made at manufacturers cost and not the end users.
Steve
100pc agree. I am currently in my MOT station and bricking it waiting to see if they will fail because of no DPF. I had little option but have it removed from my 2008 Shogun. It is flawed technology! It’s like vacuuming your home and when the bag is full then dumping the contents on your carpet. Is there anyone out there who has not had problems due to their DPF?