Aftermarket April 2022

Above: Darren Darling A ccording to Keith Shanahan, from DPF Doctor Network members Shanahan Auto Services, it is important for technicians becoming genuine DPF experts to know which questions to ask. When the customer takes their vehicle to a garage with what appears to be a DPF problem, ignorance on the part of said tech can lead to multiple return trips and unnecessary expense. This may ultimately result in a new DPF being fitted, even if the DPF was never at fault. He observed: “Our customer initially rang us to carry out an on-vehicle DPF clean on his Mercedes Benz. At the appropriate time we can facilitate this using the JLM Lubricants’ two-stage, clean and flush products, but was that needed in this case? We don’t simply take what the customer tells us is the problem.” Initial assessment Keith continued: “We proceeded, as we always do by questioning the customer about the history of the vehicle, its issues and the work carried out to date including any regenerations and additives used. As part of The DPF Doctor Network we go through a set of checks in an initial assessment. Part of this entails gathering key data, 40 AFTERMARKET APRIL 2022 TECHNICAL www.aftermarketonline.net A special focus on The DPF Doctor Network with DPF Doctor Network member Keith Shanahan, followed by founder Darren Darling checking the physical condition of several components, checking for trouble codes and much more. Questioning of the customer about their driving, fuelling, and servicing habits is also essential at this stage. “During the initial assessment we gathered enough information to ascertain that firstly the DPF was not blocked and secondly that further diagnosis of a fault in the DPF pressure sensor was required. This ultimately led to the discovery of a failed sensor which was the actual cause of the DPF trouble in this vehicle. “When the job was completed, the customer did reveal to me that he had in fact had the car plugged in at two other garages. The first garage had told him that the only option to fix the problem was to remove the DPF and map it out for only £600. The second garage said he needed a new DPF which would have cost even more. However, luckily enough he happened to meet an acquaintance at his local who suggested he contact a garage to try and get it cleaned. By chance his Google search led to The DPF Doctor Network and subsequently, me. Thankfully we were able to set him straight and at a very fair price.” “When it comes to DPF work, just bear these three points in mind. First, don’t carry out needless forced regenerations. Second, use a quality additive, if needed, QUESTION TIME