Fleet News

Drivers pouring petrol, paint thinner and oven cleaner down blocked DPFs

DPF warning light

Petrol, oven cleaner and paint thinner are some of the ways fleet managers, garage owners and diesel vehicle owners attempted to resolve blocked diesel particulate filters (DPF) during 2015, according to DPF Clean Team.

The automotive reconditioning specialist analysed the call history for its blocked DPF helpline for last year to find some of the most bizarre methods customers have used to try and unblock their DPFs, catalytic converters and silencer units.

Other failed attempts at unblocking DPFs included jet washing the filter, setting fire to the unit and even pouring oven cleaner down the DPF.

Such practices are only serving to further damage DPFs, making regeneration impossible, and significantly harming the interior of the filter.

Cameron Bryce, director at DPF Clean Team,said: “Once a DPF warning light appears on your dashboard, the worst thing you can do is pour any kind of treatment into the filter.

"Substances such as drain cleaner can remove the interior coating of the filter, stopping future regenerations from working effectively.

"The result in many of these cases is that the customer has required a complete DPF replacement, which has been more expensive that a professional clean.”

DPF Clean Team is encouraging diesel vehicle owners to seek professional advice as soon as their DPF, catalytic converter or silencer unit becomes blocked, and consider having a professional clean.

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  • Chris-p - 25/03/2016 13:21

    Proof enough that DPF systems are not fit for purpose, in which case it should be the manufacturer footing the bill for the replacement during a reasonable life mileage of the vehicle. In the United States motorists are protected by the "Federal Emissions Warranty", this forces all manufacturers to replace, at their own expense, any major emissions related component fitted to the vehicle for a minimum period of 80k miles / 8 years (120k / 12 years in some states). This warranty is a legal requirement, and is in addition to the usual warranty which comes with the vehicle. Instead of pouring chemicals into the DPF, paying £400 to have them professionally cleaned or up to £2000 for a replacement, maybe we should focus our attentions on having a similar warranty introduced into the UK on our DPF components and so indirectly forcing the manufacturers to take responsibility for the cost of their own R&D failures. At the end of the day, if the DPF systems worked properly in the first place, then there would be no need for the system to be illegally removed or circumvented or drivers otherwise take matters into their own hands in order to avoid a crippling bill on a relatively new vehicle.

    • Marco - 29/06/2016 12:56

      One of the main causes of DPF blocking is caused by something else on the vehicle. People just don't service their cars like they used to one glow plug, over fuelling injector, badly seated or failed EGR valve will have an effect on the DPF. More and more DPF blockages have underlying issues, which normally would have been picked up on routine servicing. A DPF is a filter it does exactly what it says on the tin, it filtrates. If an oil filter blocked you would not ask for it to be replaced FOC. A DPF is a serviceable item and has been since the early 80s. The USA has been cleaning filters since 2007. With all DPF replacements or cleaning, diagnostics of the emission system is key, all parts have a shelf life, sensors, glow plugs and turbo . If the car is running well with a reasonable drive cycle then a DPF won’t need servicing / replacing until it reaches about 100k, this is the crucial time when ASH accumulates in the DPF which is none combustible and needs physically removing.

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