Ignite your interest in ignition

A pair of problematic Audis reignite Frank’s longstanding interest in ignition issues

Published:  19 March, 2018

This month’s subject was prompted by a recent conversation with a colleague in Australia. The conversation included an invitation to a technical festival in October, where it was said that ignition would be one of the subjects of interest. Many years ago, when I began developing our training programme, ignition was a subject of primary concern when diagnosing gasoline
engine problems.

This is a complex subject often not fully understood and often overlooked. Its vital importance recently became apparent in our workshop, when we were presented with two Audi rs6 engine failures. One failure has yet to be investigated the other suffered piston failure due to combustion faults.

The increasing complexity of homogenous and stratified fuelling, split injection delivery and variable valve timing geometry has placed critical responsibility on ignition performance. Often within the diagnostic process there is no serial evidence of an ignition problem, or that what evidence is available is incomplete especially at the early stages of failure. The process has not changed in over 30 years;  You must scope it.

Process overview
So here is an overview of the process. Firstly, you must understand that it requires a specific amount of energy to completely combust the air fuel charge. Ignition energy is measured in joules, our task it to ensure the energy is created and delivered correctly. The primary circuit bears the responsibility of energy creation with current profile as the focus of our measurement. The secondary circuit has the responsibility of delivery, our focus is burn time and slope profile.

I accept that both circuits have a shared responsibility at the point of induction where energy within the primary is transferred into the secondary. The physical challenge is the method of accessibility. With static or direct ignition it is often not possible to connect to the coil primary circuit, leaving the option of induction as the method of measurement. The primary will always have a power and switched ground, so current measurement using a suitable hall clamp is always possible.

Diagnostic observations
The four critical diagnostic observations in order of priority are:
 
Ignition burn time measured in milli-seconds with a range of 1-3ms depending on ignition type. Do not assume length of burn relates to energy value Primary current profile with a range of 3amps (points ignition) 20amps static ignition. Note the expression profile, it includes rise time and rate of collapse Coil ringing, this is the resonance at the end of the burn event it represents the small residual ignition energy returned in to the coil secondary winding Firing line voltage, this represents the value of electrical pressure in delivering the induced energy to the spark plug electrode it includes all components in the delivery process

You must also understand that the performance of the injector, cylinder turbulence, and mechanical efficiency forms part of the combustion process. Intake air temperature, pumping losses and fuel quality all affect the burn process. Let’s begin with the tool I distrust the most! Serial data is a good first look – there is some very useful information such as cylinder misfire count, ignition timing individual timing retard data, air intake temperature and exhaust temperatures. There may also be additional data on burn time and primary charge time, but I don’t trust or rely on it.

So, out with my Pico scope. Connectivity can be a challenge, over the years we have built our own probes, however, if the manufacturers can run a circuit there you can scope it. There is a simple logic process.  Begin with burn time, look at the duration and slope it – It should be roughly parallel with the horizon.

A rising line confirms a difficult transition of energy across the electrode. Lean combustion, glazed plug, cylinder pressure, plug performance. Cylinder turbulence.

A falling slope represents the opposite condition; low cylinder pressure, fouled or shunting plug circuit, small plug gap. The burn profile should be relatively smooth, a turbulent burn path confirms difficult in cylinder conditions. It can and does point to injector fuel delivery problems especially if a sharp rise at the end of the burn time is present.

You may appreciate now just how vital scope evaluation is.

Primary current path confirms good power supply and the performance of the power transistor in its ability to switch and hold load to ground. Note the rise time characteristics and the off switch, under shoot here is a good indication. If you can, observe primary voltage. Note the slow rate on load, it’s the slow rise in voltage during coil charge time, a problem here will affect current flow so go for current first its easier to understand. Remember one of my core diagnostic rules; If it moves, gets hot, or applies a load measure current!

Coil ringing is the inverted energy returned into the coil secondary. With no path to ground,  it gradually gets weaker, converting its energy to heat. Expect 2/3 rings in current systems. If the coil windings are compromised in any way a reduction in inductance will follow. The rings will disappear, ignition energy may still be present but a reduction in value will result. Be warned this condition will never be known if not scoped and critical engine failure often follows.

Firing line voltage can only be measured accurately in primary to be honest. Expect the following values:; Conventional rotating ignition 50v, wasted spark ignition 40v, direct ignition30v; Plus or minus 5 v on all values. The problem with exploring this with a coil probe is that the probe attenuation is not known, so its difficult to scale.

I hope this helps. It is a very complex subject , often neglected and overlooked.

Just before I go here is a challenge; How many information systems, VMs especially, don’t give these four  vital statistics? So how do they know if there is a problem?



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  • Hats at the ready! New tools available 

  • Hello can we talk? 

    I have been known to say that “Communication is a wonderful thing." Usually the context of this statement is that there has not been good communication and it has resulted in one or both of us missing something or being agitated with one another for not communicating well to the other what was intended.
        
    Probably sounds familiar to many of you, but in the business context it is vitally important that you can communicate with your customers in a way that conveys professionalism and instils both confidence and trust. This is ever-more difficult against a background of increasing vehicle technology and decreasing levels of technical understanding from your customers.
        
    At its most fundamental level, effective communication is the exchange of thoughts, information, ideas, and messages between people. However, it’s not communication unless the transmission is understood. Communication can happen verbally, nonverbally, in writing, and through behaviour as well as by listening and using feedback.
        
    No matter who or what audience you address, the art of communication can be a daunting task – as indeed, it is an art form. The good news is that there are seven steps to clear and effective communication for even the most challenging conversations with customers when trying to explain what is wrong with their vehicle.

    Strategies
    So how can you communicate effectively in this increasing technical environment? One of the best ways is to imagine that you are talking to your grandmother – she may be a little slow to understand, is very non-technical and is going a little deaf!
        
    Keep it simple: Think about how you can make the complicated simple. Do not use highly technical terms or technical abbreviations and explain slowly and clearly. A good example would not be to say: "Sorry, but your EGR valve is blocked by carbon build up on the pintle needle so now it can’t control the correct NOx requirements." Instead, say: "There is a valve on your vehicle’s engine which is required to control exhaust emissions and it is not working correctly." If the customer wants to know more you could always add: "Because it is blocked by carbon build up from the exhaust system, as it recycles exhaust gasses to reduce the exhaust emissions."

    Simples! – as they say.
        
    Does it make sense? Always ask yourself; Does what I’m saying make sense to the person I am speaking to and subsequently does the feedback I’m receiving confirm that they have understood?. When both parties in the conversation are truly able to say they understand or that it is all clear  effective communication has been achieved.
        
    Failure to Communicate – it’s down to you: Remember, as the primary communicator you are 100% responsible for the other person’s understanding of the communication. In other words, if you don’t feel that you are being understood, you have not completed the job of communicating. Don’t try to change what you are trying to communicate, but how you are communicating it.
        
    Stay on Message: Be clear about what ideas you are trying to express or the message you are trying to convey to the other person. What do you most want them to understand?
        
    It takes two: Try to really understand where others are coming from. What are they trying to say? What messages are they trying to get across to you? Pay special attention not just to what they are saying, but to what isn’t being said as well as their body language. Finally, if in doubt – ask!
        
    Sorry, what did you say? Do you really hear what others are saying? To really listen you should stop everything else that you are doing and really listen to what is being said to you. You should then summarise your understanding by being able to feed back to them exactly what you have understood them to have said. Good communication is a two-way thing.
        
    Respect: Recognise that your message is not just about you or what you want. It’s about what’s in it for the listener.  You must mutually understand what is being said and the corresponding implications. After all, they took the time and trouble to hear what you have to say, so it’s equally important to recognise and respect that we each have different perspectives based on our positions, motivations, and needs.
        
    Good communication for technically difficult aspects is a combination of both ‘what you say and how you say it’. In summary, keep it simple, keep it short, be a good listener and be both respectful and empathetic. Above all, avoid being condescending.

    In writing
    When communicating in writing, ensure that you are concise, that you write clearly about the specific point and consider that if you were in the recipient’s position, would they understand what you have written, especially in all the points that they need to know from you. Your audience doesn't want to read six sentences when you could communicate your message in three. Read what you have written and delete any words that are not needed to clearly explain what you need to say. Less is more, as long as you include everything you need to say.
        
    Effective written communication ensures that the audience has everything they need to be informed about, and if applicable, take action. If your message does include a 'call to action', does your audience clearly know what you need them to do?

    Good example
    As an example of good communication, I use a local independent workshop and Keith, the manager, is the epitome of how it should be done. It goes something like: "Hello Neil, your car is in today for a full service, so we will need it until around 2 o’clock. Can I have the key please? Is this mobile number the best to use so we can call you if I have any questions or to let you know when it is ready and finally is there anything else you would like us to know about that we may need to look at today?" Followed by my reply: "Great Keith, no, nothing else, so many thanks and see you later."
        
    Quick, polite and concise. When I pick my car up, he uses similarly simple and clear language to explain what was done, advice on any other issues they noticed before explaining the invoice, asking if everything is clear or are there any questions before requesting payment. Importantly, Keith never tries to baffle his customers with technical terms and avoids being condescending – important points in the key areas of creating professionalism, confidence and trust in this increasingly technical environment. It is a bit like your grandmother saying that the simple things in life are often the best and this applies to good communication when talking technical.  

    xenconsultancy.com

  • VXPRO ignition coills 

    With more than 300 part numbers, the VXPRO ignition coil range includes many items that workshops will need when working on ignition systems. An ignition coil is wire wrapped around a core to make a transformer, which converts the low voltage from the vehicle’s battery, to the thousands of volts needed to create an electric spark in the spark plugs. They are of various types including older style oil filled wet, as well as newer, distributor, block, pencil and rail coils. ELTA provides a range of options through the VXPRO range.  
    www.elta.co.uk

  • Get to the essentials 

    Marketing can be hard to grasp, even for the most experienced business operator. This made it an ideal topic for Andy Savva to cover as part of his 2019 training course schedule. Andy's one-day Marketing Essentials course provides an overview of what marketing actually is, looks at key approaches and how to apply them to a garage business.
        
    Aftermarket sat in on a sold-out session held in Crawley in February. In front of a packed room, filled with garages owners and staff, Andy dispelled some myths and misconceptions surrounding the discipline: "Marketing is one of the most misunderstood functions found in business. Whatever the reasons for any negative image that marketing may have, it is essential to realise that marketing is vital to ensure the survival and growth of any business. Marketing cannot be ignored and needs to be a part of the culture of any successful organisation.
        
    "Marketing affects everyone. We are all consumers. Most businesses depend on marketing to provide an understanding of the marketplace, to ensure their products and services satisfy the needs of customers, and that they are competing effectively."
        
    Despite running great businesses, Andy has found that garage owners often struggle when it comes to marketing: "Understanding customers and anticipating their requirements is a core theme of effective marketing, yet this is somewhat difficult for garages to fully get to grips with. So too is understanding general market trends and developments that may affect both customers views and the activities of businesses in the aftermarket repair sector. You must also be aware that a business does not have the marketplace to itself. There are always direct competitors, new entrants and indirect challengers.”
        
    Andy added: "Marketing should concern everybody in a business as it sets the context in which sales can take place. Whatever your role, you play a part in setting that context."

    Interaction
    As Andy got into the meat of the marketing matter, he led the delegates through what marketing is, and how they need to approach it and enact effective marketing within their businesses. Even the most experienced business owners and managers can get a little confused when asked to distinguish between marketing, advertising and sales. After asking attendees to pick where they would plant the marketing flag, with a few near misses along the way, Andy went through the specifics:
        
    "Marketing is a systematic approach aimed at bringing buyers and sellers together for the benefit of both. Many people confuse selling and advertising with marketing but they are not the same. Marketing is about promoting goods and services that both satisfy customers and also bring profits to the business.
         
    "Selling is the interaction that takes place on a personal level with potential customers. Marketing on the other hand is aimed at generating those potential customers in the first place. Many people confuse selling and advertising with marketing but they are not the same. Advertising is part of the marketing function, but never the other way around."
        
    For marketing to succeed, there needs to  be a goal and a way of achieving it, which Andy went on to cover: "Any marketing campaign needs to have a clear focus and this is why it is so important to make the right choices. Will the business compete across the entire market, or only certain parts? It is also a good idea to ensure all employees know the strategies being adopted, so that everyone works together to achieve the same goals." Andy then asked a question of the group: "Do you know what your garage business is trying to achieve and how it is trying to achieve it? In most cases the answer is no."
        
    The goal influences the method, and vice versa. From this point, Andy covered the classic four Ps of marketing – product, price, place and promotion – and went from there to the more recent extended marketing mix, incorporating people, process and physical evidence. Beyond this he laid out transactional marketing, which is sales-focused, and relationship marketing, which takes a much broader view including customer service, and quality presentation and results.
        
    Next he took on the thorny issue of branding as part of the marketing strategy, and why a strong brand is so important for recognition, financial value, motivation and loyalty. All of that was just the pre-lunch session. After lunch, Andy went into even greater detail on areas such as the marketing triangle, SMART objectives and SWOT analysis. It's heady stuff, but Andy made it approachable and applicable to the sector.

    Inspirational
    Those in attendance found a lot to take away from the day. Dani Comber from Thrussington Garage in East Goscote, near Leicester said: "I find Andy really inspirational. I think he's brilliant. He can come and work at our garage." Commenting on what she was learning about marketing from the day, Dani said it showed the gap between what they were doing at present, and what they should be doing: "I find it demotivating and motivating at the same time. You want to do everything, you've got the intention to do it, but you've not done it. On the other hand you are motivated because you see what you can do."
        
    Elisa Bramall from Scantec Automotive from Hailsham, East Sussex said: "I have attended several training courses with Andy. I only have good things to say about him of course. His passion being the main thing, and that he says it how it is. No beating around the bush. A lot of his values we stand by as well, i.e use of OE parts, tools and genuine equipment. When you attend his training courses, it aligns with what we want to achieve. With all of his experience, if you think you know it all you certainly don't."
        
    Tina Drayson, Operations Manager at CCM Garage, based in West Sussex and Surrey said: "I have done Andy's financial course before. It is phenomenal. I have learned so much from it. It has certainly changed the way we are doing our business. I am hoping that today with the marketing essentials will give us even more direction going forward."
        
    Terry Roberts, owner at  Witham Motor Company in Witham, Essex said: "I have just become a RAC approved garage in the last few weeks, so I am looking at changing my brand. I am really enjoying it. I am learning a lot and have picked up a lot of things."
        
    Commenting on what he was getting from the course, Billy from  Beacon Hill Garage in Hindhead, Surrey said: "It just hammers home that if your standards slip, and your marketing as well, and you take your eye off the ball, things will go wrong. I will be going back to give a few people a kick up the backside to bring standards back up. "
        
    Brothers Mahesh Vekaria and Pravin Patel own a garage each in Harrow. Mahesh, owner of Cardoc said: "What have I learned from Andy today so far? It has refocused and re-energised my enthusiasm for marketing. We do a fair bit of marketing, but coming today, you see a different angle to it."
        
    Pravin, proprietor at Harrow Service Centre, observed: "Today has been interesting. I have learned a lot. In a sense we already do a bit of marketing, but to understand what it really does mean and the ways we are doing it – is it right or wrong? – is really useful. It is something to implement when we go back to work."
        
    In that the pair are brothers and are based just half a mile apart, Aftermarket was curious as to who would get back and implement new marketing initiatives first. "I would say that I would," said Mahesh. Pravin agreed: "Yes  he would, definitely, having said that, he looks after my marketing for my garage as well. So he has double the work really."

    Information
    Edward Cockhill of Uckfield Motor Services in Uckfield East Sussex observed: "It is quite an eye-opener. I saw marketing as just advertising, whereas it is really the whole perception of my company. There is a lot of cogs that are going to be turning when I get home. "
        
    Peter Bedford of GT One Ltd in Chertsey, Surrey said: "We are an independent Porsche specialist. Our business is in need of a bit of a review in its marketing ideas, and we are looking to freshen it up. I have come along to see another angle of it. Some things I think I know and we have applied. Some I know and we have not applied, so you need a kick up the backside. Some things are brand new. On the whole it is brilliant."
        
    Cieran Larkin from Larkin Automotive in Dublin commented: "It is good to get marketing training from a professional who has been in the garage business as opposed to someone who is dealing with generic marketing. Andy's experience is brilliant in that way."
        
    Nick Robinson from Marchwoods in Folkestone had been to Andy's courses previously and was back for more: "I came to Andy's events last year for garage financial understanding and customer excellence. They were real eye-openers so I have come back for another one. I was badgering him earlier to see what is coming up next. I will be at that one as well!"
        
    Meanwhile, for Edward from Swanley Garage in Swanley, it was his first time: "This is the first one I have been to. It is really good. It is about getting all the information and having the guts to go out and do it. We are all guilty of not doing marketing properly, it is about taking that jump to rebrand yourself or say right we are not doing that any more, or we are not doing cut price work, or we are not going to let the customers bargain with us any more, and seeing where it takes you."

  • Would you like to diagnose more vehicles first time? 

    As we reach March, 2019 is well and truly underway. In fact by the time you read this one third of the year will have whizzed by never to be seen again. Now, I’m not one for New Year’s Resolutions (they’re so last year), but I am the type of chap that likes constant progress when it comes to developing a technician’s career.
        
    There’s so much to be said for small steps taken everyday that on first look appear don’t appear to make a difference, but when gazed back upon over a 12 month period have a staggering affect on your capability to diagnose a vehicle first time, in a timely manner.

    Pitter-patter of tiny feet
    Small steps are all well and good but where do you start? After all, you don’t know what you don’t know, and you’d like to start your journey to diagnostic success off on the right foot. In this instance I’d start with the end in mind and reverse engineer the outcome you desire. It’s a logical process that works, and can be replicated time and time again in your diagnostic routine.
        
    Your ‘end in mind’ in this instance is a vehicle where the fault no longer exists, that won’t appear back across the threshold of your workshop anytime soon. But how do you guarantee that?

    One test to rule them all
    I love nothing more than when the delegates working through our training programs have a technical epiphany. This happens at many points on their path of learning, but none more than with bypass testing.
        
    Bypass testing is step nine in Johnny’s diagnostic circle of love (our 15 step routine), and often the key element in the first time fix. The good news for you is that it doesn’t require mythical creatures to forge their magical powers into an object that only one technician can possess. It’s something that every tech can learn, and become a diagnostic wizard.

    What is bypass testing?
    Quite simply it’s fixing the vehicle before you fix the vehicle. Let me explain.
        
    Wouldn’t it be great if you suspected that a Mass Air Flow sensor was at fault and you could prove that you were right before you fitted a new part, or spoke to the owner of the vehicle. If you could do that then the positive effect it would have on you and the business you work for would blow you away.
        
    Picture this: Your customer has reported that the vehicle is low on power. You’ve diligently questioned them, experienced the problem with them on a road test, and the bought the vehicle into the workshop.
        
    You’ve pulled codes and found none present, followed by taking a look through serial data to hunt for diagnostic clues. It doesn’t take you long to identify that the MAF sensor frequency looks a little low at 1.5 Khz and your fuel trim data is incorrect and making a positive corrections. You’ve seen a bunch of these before and know that 1.85 Khz is a suitable value for this vehicle.
        
    You’re keen to prove that the serial data is leading you in the right direction so confirm the sensor output with your oscilloscope. The oscilloscope frequency mirrors that of the serial tool and your starting to get that warm fuzzy feeling that an you’re onto something.

    Steady the buffs
    You’ve been close to success before though, only to be thwarted in the final moments so you’re keen not to be caught out twice. You know that documenting the reasons that the MAF output could be incorrect is the way to go, and duly make a list of tests required to confirm your theories.


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