The future of DPF servicing

Change can seem shocking at first, but is it the future?

By Frank Massey | Published:  08 May, 2017

Two months from now will bring my tenure in the motor industry to 49 years. I would like to think I have evolved, kept up with technology, enabling me to provide a professional service, enjoying customer respect and integrity. My focus has been the technical challenges, while my son David manages the commercial responsibilities.

This creates a wide role for me developing our training programme, internal research and development, bringing the focus of this topic to technical and legal compliance.

My chosen subject here is diesel servicing and repairs, specifically particulate filtration and emission control. It is something we have been passionate and vocal over for several years. it gives me no pleasure or satisfaction in seeing our prediction over the demise of diesel vehicles.

Diesel fudge

The future is now clear as to the changes our political lords and masters have in mind. This gives us a short timeline to get our house in order. My intention is to advise, help and warn what will happen if we all continue to fudge diesel particulate repairs as we currently do. Upwards of 90% of independent garages will fall into this category. How do, or should we service and recover diesel particulate filters? The choices are very simple!

1. Replace with a new OE filter

2. Replace with a non-OE filter

3. Clean and service off vehicle in factory controlled conditions

4. Clean and service off the vehicle in house

5. Clean and service on the vehicle

6. Remove the filtration system from the vehicle

Here is the problem; we as professional repairers are legally and financially responsible, and exposed for the advice and decisions we make. This is the case even if the customer agrees and or instructs us on a certain course of action.

Clear legislation is in place for the performance and fitment of diesel emission systems. Vehicle taxation is based on specific emission levels agreed with the manufacturers. I am sure I do not need to mention VW and Audi, but I will bet their corporate accountants have regrets. How long do you think it will be before the government bean counters look at us? Let's not fool ourselves enforcement will take the effect of stringent fines.

Everything

So what are we doing wrong? Pretty much everything. Please remember my words, help, advice and not critique.

We are breaking the law in removing legally compliant systems. MOT examiners will lose their licence by passing unauthorised emission system modification. You will become the first unpaid enforcers.

We are breaking the law further in polluting the water course, by power cleaning, or rinsing out cleaning agents into the drains. Utility companies have powers to set huge fines and often do.

We are also in breach of the clean air act by using some of the available cleaning agents that require the running of the engine whilst emitting all the contaminants back into the environment.

It is quite possible at this point some of you are about to rip out the magazine pages and offer an alternative use for them. Please reconsider, we are slowly killing ourselves.

Let's as an industry get together, think ahead of the curve and get our house and process in order.

Change

I recently visited CERAMEX in Slough, and before a handful out there suspect a paid endorsement here, I even paid my own travel expenses. I have been aware of several companies offering off vehicle cleaning, pressure washing, thermal cleaning in an oven, and ultrasonic treatments. My problem has always been, is the catalytic converter and DPF still fully functional and durable when refitted? How can we protect ourselves from future premature failure due to other indirect causes? Can we provide certification of test results?

Here is my opinion as to how we should address the blocked, cleaning DPF problem. Many of you will not agree, I do not care, this is how it should and eventually will be done. Reflect on the vast changes in the paint refinishing industry before you cry never!

The DPF is initially visually examined bar coded and weighed, attached by means of bespoke plumbing to what is in effect a big dishwasher (sorry Marcus my words) then filled with water. A short pause here, some of you will know water damages and degrades the precious metal wash coat. The purified water has all the damaging trace elements removed and is only used to restrict the clear DPF passages. Pressure waves, are then sent through the core, XPURGE for several minutes. I did question if this was in effect an ultrasonic process? This is not the case. The water does act as a transport mechanism for the waste material, including ash, which is flushed out, into a waste tank. The water is filtered, for reuse and the semi solids captured in large skips for reprocessing. It is pure carbon it would make an ideal fuel source!

The DPF core is then placed in electric air dryers where apart from drying the core, measurements are taken for flow rates and back pressure. Next a two-stage photograph examination is applied to detect face off and ring off cracking to the core. A second weight check is taken to ascertain the mass of soot ash removal. The next service is optional for small vehicle units, the cat and DPF are subject to a sample hot gas bench to establish the reduction of, CO/HC, finally being placed in a particulate bench where filtration is assessed and measured.

Certification

Certification and bespoke transport packaging completes the service. The recovery success is consistently above 90%. The cost is approximately half the cost of a new OE unit. No environmental pollution so your grandchildren will thank you and may avoid the huge increase in paediatric respiratory illnesses.

You will earn profit from a professional repair, enjoy the respect and integrity it brings, however not all customers will agree or want to pay, and that is not our problem.

Further information

Please contact Annette 01772 201 597, enquries@ads-global.co.uk for further information on upcoming training courses and events.

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  • Tools to survive and thrive 

    My life as a business owner, trainer and technician is an interesting one. I was recently spending some time with a client after a course just shooting the breeze. You know the kind of thing, a cuppa, a cake and an hour just putting the world
    to rights.
        
    Part way through our conversation Matt proclaimed that I must be “living the dream!” This made me stop and think (something I’ve been told not to do by my wife) about how I am indeed very fortunate to have a career doing something I truly love.

    Wading through treacle
    Spending my days with like-minded business owners and technicians, helping them drive their careers and businesses forward. What’s not to like about that? Not much, but has my work life always been like skipping through meadow on a sunny day?
        
    Quite frankly… No! Don’t get me wrong –  I’m a glass half full sort of chap and regardless of the task ahead I’ll give it my best and persevere until success emerges. However, on many occasions in my diagnostic career it was just like wading through treacle, and therein lies my point. To get to a place where you’re ‘living the dream’ you need wellies! Show me a successful technician and I’ll show you someone who’s great at wading. They’ve just waded long enough to build a versatile skill set along
    the way.

    The recipe for success
    As with most things in life there are essential ingredients. With the right ingredients you’ll successfully avoid the diagnostic treacle swamp and swap this for a faster and more enjoyable repair experience.
        
    “What’s this recipe?” I hear you cry. It has six elements that when bought together produce truly remarkable results. They are;

  • Expert training, Italian style 

    I have just returned from Modena, delivering a two-day advanced technical training seminar to 21 of Italy’s top independent technicians. I was travelling from across Italy and beyond, attending PCB Automotive’s international training programme, focusing on gasoline direct injection and common rail diesel.  

    The essence of the training was the advanced application of Pico oscilloscope to diagnose and gain predictive evidence for a repair solution. The technicians were particularly interested in the techniques of high pressure pump testing pioneered by ADS several years ago.

    Attending the event were diesel and gasoline specialist and Italy’s most respected Bosch trainer. No pressure then! The session began with an explanation of the importance of scope performance when gathering data at high resolution requirements. Acquisition, storage, display, test lead bandwidth and advanced triggering with math channel analysis.

    As expected Bosch had a different political agender towards our pump proof testing. It was however received with enthusiasm and great interest once its accuracy and simplicity was experienced.

    The session on ignition evaluation was of great interest especially when focusing on primary current ramping and slew rate. Further discussion on burn time and slope completed the morning session.

    The four-course lunch was a typical treat of local Italian hospitality and cuisine. The afternoon session included the evaluation of load request with air mass and Lambda response. By comparing response and rise time evaluation it is possible to predict and confirm complex fuel delivery and combustion anomalies.

    A full eight-hour day concluded with hybrid cart racing north of Bologna, followed by the inevitable pizza and Mr Moretti’s finest.

    Data and interest
    Day two and common rail diesel with a similar agenda,   with a strong focus on Math analysis of pressure and volume control against fuel delivery pressure. We have accumulated a vast database of rail pressure profiles, rise and decay times across all diesel manufacturers. This was of great interest to a Bosch pump and injector repair specialist. Approving nods and smiles throughout supported our confidence in this form of diagnostic analysis.

    There was great interest in the examination and influence of rail pressure and air mass response time.  Converting digital air mass into a current profile enabled delegates to understand the speed and simplicity with which a technician can determine the source of an error, either hydraulic or sensor input.
    The day concluded with certificates and a photo session. Teachers usually get apples from students so imagine my joy with a bottle of wine and finest olive oil.

    With a 6.30am flight in the morning and 50 kilometres back to Bologna, it was a very nice gesture from Luca my host to take me for a special evening meal at a villa outside Modena.

    I found it intriguing to be asked by several of the delegates, with my international training experience, where the best technicians are to be found. I responded including them with the very best, not just because of their technical fluency, but especially their mutual respect and co-operation with each other, sadly lacking with some in the UK.

    Using Math
    To conclude let’s look at an example of using Math to predict hydro mechanical function against rail pressure.
    The system example; Bosch cp1h, volume control single point, solenoid injectors. Sample taken from stable idle, part load snap open throttle, return to idle.

    Channel a blue;
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    Channel b red;  
    Volume control valve ground duty control

    Channel c green;  
    Volume control valve, current vis rail pressure

    Channel d black;  
    Air mass meter profile vis rail pressure

    Math Channel purple;  
    Math duty volume control

    The focus of this analysis was to establish the rail pressure hydraulic response time against air mass load signal, expressing the primary control device, volume, as current and math duty conversion.

    To understand the values in this test enables an unequalled understanding of the systems capability in delivering fuel vis time.
    The next challenge is to sync a second 4 channel scope monitoring compression using WPS, with the 4-stroke cycle overlay, noting the secondary pressure increase when fuel is injected. Then we really are ahead of the curve.



  • can you feel the wheel?  

    I’m pleased to be writing a second article and this time I’ve decided to look at the active wheel speed sensor.
    Originally electronic anti-lock braking systems (ABS) used magnetic inductive sensors to measure wheel speed. These are classed as ‘passive’ sensors and are actuated by a rotating toothed ring. The sensor contains a magnetic core w1 vith a fine coil of wire around it. As each tooth passes the sensor it generates an alternating current (AC) analogue signal. The faster the wheel goes, the greater the frequency and the higher the voltage. The wheel speed is determined by the frequency. The main disadvantage of this is the weakness of the signal at low speeds.  

  • No Smoking! 

    There’s nothing I love more than picking up an automotive magazine and reading a good case study. Occasionally they may be talking about a specific fault you’ve seen before. Sometimes as you’re reading through the symptoms and evidence you can’t help but make your own diagnosis and see if you were right.
        
    The most engaging ones for me are when it’s not a common fault and you follow the diagnostic process of the writer. I find I always gain ideas and tips from a lot of these articles which assist me in improving my diagnostic success rate. In my previous articles I’ve emphasised the importance of training, whether it be in the classroom or via CPD. Another key thing is to learn from our mistakes and recognise our weaknesses. If we don’t do this, how do we improve?

    Patterns
    Over the years we have developed a good reputation for diagnostics which regularly brings in new customers. So when someone phones and says “I’ve got a light on and I’ve been told that you’re the man to see,” we have to make sure we get it right. When that sentence is closely followed by “my local garage has replaced some parts but the light has come back on,” we can quickly guess what’s coming next; “Can you fix it? I’ve already spent hundreds, how much is this going to cost me?” We’re not guilty for the previous garage’s failure to diagnose the fault but if we agree to take on the job we are compelled to get it right and so we should be. When you do get it right, is it necessary to stick the knife in the other garage’s back? Of course not! We always try to be positive and stick to explaining why we were successful with the repair rather than why the other garage failed. At this point you’ve already won the customer’s confidence in you.
        
    So we learn from our mistakes and we can also learn from other people’s mistakes. With this in mind, over the last few months I’ve looked for a pattern in why misdiagnosis seems to occur. The obvious answer here is lack of training and skill but the frustrating thing with a lot of these jobs is if the technician had just stopped for a minute and thought about it, they probably would have found the fault.

    Information
    I’ve picked a handful of the last few jobs where this is the case and I’d like to share them as case studies.
        
    The vehicle in question: 2012 Ford S-Max 2.0 Diesel. The customer’s complaint: Engine malfunction light on and lack of power. Previous work carried out: New genuine Ford mass airflow sensor fitted.
        
    As always, we gathered as much information as possible from the customer. A key piece of information here was that the vehicle starts fine with no light on and performs normally until you accelerate hard or go uphill. He said his local garage plugged it in to their computer which told them it was the mass airflow sensor. They replaced this but it didn’t fix the fault.
        
    We read the DTCs from the powertrain control module (PCM) and then road tested the vehicle to confirm the fault. The DTC was ‘P00BD-00 Mass or Volume Air Flow “A” Circuit/Range Performance – Air Flow Too High’ Yes, that’s a bit of a mouthful but there is an important clue in there. In this case we cleared the code just to make sure it returned when the symptom occurred which it did.
        
    At this point there are several ways to go dependent on what you have access to.

    Option one:
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    Option two:
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    Option three:
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    Someone has already tried option three  so let’s forget that. We don’t all have option one but I highly recommend having it in place as it can be extremely useful and save a lot of time...   

    ...We chose option two.

    Sensors
    As we were already on road test it was an ideal time to look at some PCM serial (live) data. We opted to look at the mass airflow sensor (MAF) and boost pressure sensor/manifold absolute pressure (MAP) sensors signals. Most diagnostic tools will give a ‘desired’ and ‘actual’ reading of MAP. Desired is the reading the PCM is requesting and expects to be seeing and actual is what is actually being measured. This regularly proves to be very handy when diagnosing any air/boost related faults. Straight away we could see that when you tried to accelerate, the actual boost pressure was considerably lower than the desired pressure. There are many possible causes of low boost pressure. We tend to start with a pressurised smoke test to the induction system. This is
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    Experience
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    Experience has taught us that different manufacturers have different ways of saying the same thing and that is why I emphasise on reading the fault code carefully. For the same symptom some manufactures may use the fault code text ‘boost pressure too low,’ ‘boost pressure negative deviation,’ ‘turbine under-speed,’ the list goes on but this one: MAF/MAP correlation incorrect”’(seen on Land Rover) hits the nail on the head! The logic within the PCM relies on tables of pre-set data for comparison. It knows that if the engine speed ‘X,’ if the air mass entering the engine is ‘Y’ then the manifold pressure should be ‘Z.’ There is a set error tolerance either side to allow for slight deviation and when this is exceeded. For example, when air is passing through the mass airflow sensor but escaping before the manifold, then the DTC is set and as in most pressure related faults the engine power is reduced (see image 4).


  • THE WINNER TAKES IT ALL... 

    Workshop owners need to think hard about investment decisions. With that in mind, I’ve used my last two articles to look at a business management tool called value proposition design, which can help us to work out where to spend our cash.
        
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    Our investment decisions are usually complicated by the fact that they can represent a chicken-and-egg situation: Money is needed to support the creation and delivery of products and services, yet profitable products and services are needed to create money (at the very least you will need to show that you will have good profitability if you are borrowing to fund your investment). As such, there are two measures of success of our value proposition: Whether it provides real value to our customers and whether it can be deliverable within a sustainable business model.
        
    This article introduces a concept known as fit, which is the extent to which a company’s offerings match the needs of its target customers and are delivered within a sustainable business. Fit, therefore, represents the yardstick by which the success of a value proposition is assessed.
        
    There are three levels of fit of a value proposition to a customer (segment) profile:

    Problem-solution (‘on paper’)
    If we take the value proposition discussed in my last article and check it against the customer segment profile created in the preceding article, we can check their fit. We do this by going through the pain relievers and gain creators one by one and checking to see whether they match a customer job, pain or gain. We can physically visualise this degree of fit by putting a check mark on each one that does (see Figure 1).
        
    In this example, we have used our experience to the identify some jobs, pains and gains that customers might care about, and then created a value proposition to try to address them. However, at this point, we do not have any material evidence of the potential success of these products and services, gain creators or pain relievers. I.e. the fit is only evident on paper. The next step is to find evidence that customers care about the value proposition, or to start over designing a new one, if it is found that the customers don’t care.

    Product-market (‘in the market’)
    Once your products and services have been made available to customers, you will soon see whether they provide value to your customers and gain traction in the market place: customers are the ultimate, most ruthless, judge and jury of your products and services.
        
    When assessing product-market fit, it is important to check and double-check the assumptions underlying your value proposition, i.e. have you correctly identified and prioritised the relative importance of the customer’s jobs, pains and gains? Have you provided things that customers don’t care about, and will you have to amend your value propositions, or start again?
        
    Business model (‘in the bank’)
    Your business model is the way your business is geared up to generate revenue and burn cash whilst you are creating and delivering a value proposition to your customers.
        
    The search for business model fit involves reaching a state where you have a value proposition that creates value for customers (products and services they want) and a business model that creates value (profit) for your organisation. You don’t have business model fit until you can sustainably generate more revenues with your value proposition than you incur costs to create and deliver it.

    Context
    The potential value of our products and services, and the associated gain creators and pain relievers, doesn’t just depend on their match to the customer’s jobs, pains and gains. It also depends on the circumstances in which they are offered; i.e. their value is dependent on context.
        
    For vehicle owners, an example might be the value of breakdown services. Have you ever signed-up for these from the hard-shoulder of a motorway? You’ll notice that you don’t get much of a discount. Those offers that you might have seen on the internet beforehand will suddenly seem pretty good value. These differences are because the breakdown service companies know full well that the perceived value of their services depends on context!
        
    As such, businesses must identify the contexts in which their products and services will be offered. For example, a customer’s priorities will differ depending on whether they are broken down, have an expired MOT, need a replacement bulb in night time driving conditions, or are just booked-in for scheduled servicing etc. It is possible that each context might require its own value proposition.

    Focus
    For a customer having a given set of jobs and associated pains and gains, there are many ways a business might design a value proposition to achieve a fit. This is certainly true in our industry, in which there are many competing types of service and repair provider. Each has tweaked its value proposition to suit a given type of vehicle owner or context:

    Independent workshops, often offering a large range of products and services as a kind of one-stop-shop to the ‘general’ motorist, usually aim to generate sufficiently high revenues by inspiring maximum loyalty from customers and trying to meet all their needs under one roof. These businesses require constant investment to provide the services necessary to keep-up-to-date with changes in motor vehicle technology and face a continuous challenge to monetise the value of every additional service.  Many diagnostic (or recalibration) services are still not well understood by customers, and workshops have to work hard to educate them, so that they can ‘appreciate’ their value. Convenience must also play a relatively significant part in their value proposition.
      
    Fast-fit operations are all about convenience: Their customers can get in and out fast, without any notice, and, hopefully, with the minimum of disruption to their lives. The businesses require large stock inventories to ensure that there are no supply-related delays. By concentrating on only the fast-moving (the most commonly needed) products, these businesses can remain highly scalable and profitable: although they limit the scope of their products and services, to reduce costs, their sales volumes allow them to retain considerable buying power. Their customers love the convenience and prices they can offer given the buying power (and increasing integration with the parts supply chain) that the larger fast-fit chains have. Main dealers, I think, rely more on social or emotional pains and gains to draw in their customers (e.g. think about the image they work hard on purveying or the potential manipulation of customer perceptions of safety, both driven by presenting themselves as the most qualified to work on a given make of vehicle). They need to work hard to offer convenience (e.g. courtesy cars, rapid turn-around, customer/vehicle pick-up or drop-off etc.) as their dealerships, geographically-speaking, are relatively sparsely distributed amongst the population. Some vehicle owners (ironically, those most likely to buy their next vehicle from a dealership) will also be concerned with the resale value of their car and may seek to maintain a full dealer service history to try to maximise its value.
        
    Following the above, broadly-defined, categories of businesses, there comes specialists, offering a smaller range of products and services to increasingly niche customer segments or contexts: e.g. independent specialists (single-make specialists combining aspects of both the independent workshop and main-dealer value propositions), diagnostic specialists (as with breakdown and recovery specialists, when you need them, you need them – and they should charge accordingly), component-repair specialists (e.g. transmission specialists).
        
    Then there is the remaining plethora of value propositions available to vehicle owners: breakdown and recovery services (apart from their normal role helping those in distress, I’m sure they would agree that they also play a role in repairing vehicles for those that place no value whatsoever on preventative maintenance…); mobile technicians (perhaps offering the ultimate in convenience in certain contexts?); and, my favourite, the chancers (that bloke in the pub who once changed a side-light and now thinks he can charge an equally stupid idiot to fit a new timing chain for them…).

    Future
    We’ve seen from the above that a stack of value propositions is competing for our vehicle-owning customers. As such, our value proposition design work and derived knowledge, can inform a strengths, weaknesses, opportunities and threats (SWOT) analysis of our business. So far, all these competing businesses have managed to co-exist and thrive within an industry that is set-up to offer value to private vehicle owners. However, take a look at Figure 1 again – what might be arriving in the future that could represent a threat to not only an independent workshop but the entire sector? How about Vehicle-as-a-Service (VaaS), a.k.a. car-on-demand? This single value proposition removes an awful lot of the hassle of vehicle ownership (equivalent to automotive morphine…) and provides many gains. In fact, it is so disruptive that it removes/changes the very nature of the customer segment; vehicle ownership becomes almost redundant. Should it be a surprise that one of the few barriers to widespread adoption of VaaS (the convenience of making short, necessary, journeys, e.g. to pick up milk when nearby shops are closed) is being addressed by a company that is seeking to provide VaaS: i.e. Amazon whom are also developing drone delivery systems?
        
    When it comes to the ultimate value proposition, may be there can be only one.
        
    I’ll leave that thought with you.


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