Stevey Y

If you search the A6 C7 and the A4 parts of the forum there are more than enough posts on the subject, it probably is a wiring fault and from memory a couple of them just bypassed the switch just to get a running vehicle, you might have to go back a couple of years but if you get stuck ask Gareth [Magnet] and he has an uncanny knack of pointing people in the right direction. Steve.

Hi Steve, sorry to hear of your problem which is not unusual the system is badly designed, I am assuming its the level sensor that is the cause of your problem that is housed in the tank all other sensors/heating elements are in the pipework that runs from the tank, therefore if the tank is depleted get it refilled and at the same time get a level reset done by a VAG specialist as I have a theory thats why they asked you to run it down until it wont start, the wont start bit is activated when the Sensor realises there is not enough adblue, have you any fault codes to offer as that may give some illumination to the problem, as for customer service there is more chance of the Second Coming, if you use a VAG specialist even if you do get it replaced it will be cheaper. Steve.

Hi you say the car has full service history, is it Audi ?, unfortunately the diagnostic system you use only picks up the fault codes but gives no indication of when or the frequency of the fault, I say this as these vehicles have a nasty habit of hanging on to redundant codes, therefore clear all codes and run it for a few days then scan again and see what comes back, also have you checked the pressure sensor flow readings and the ash content of the DPF as all of these will have a bearing on the engines breathing, from experience these engines rarely do what the maker claims not forgetting its a heavy car, is it an auto? as that wont help, the main priority is to check things such as battery age as some of these faults could well be low voltage, the fresh air sensor is a painful one as if you buy a new one [not cheap] it will be exactly the same within a year they are simple to remove and soak in isopropyl for an hour and they come back to life, if you intend to keep the car I would seriously consider a better diagnostic device. Steve

Hi nothing new on the later models except that they still use the flawed sensors, what rocket scientist thought it was a good idea to use something that has the reading connectors exposed in boiling oil, as long as you haven't topped it up at all if anything it should only show low, this and the great idea of having a sensor on the bonnet catch that throws its toys out of the pram if you open the bonnet again after servicing the car the sensorial show empty because thats the last reading it had after you had drained the oil, either way Cliff is right they will have to fix it. Steve.

Hi blocked heater matrix possibly have you checked the expansion tank to see if the silicate bag has broken in which case you will find the bag absent silicate, that will be floating round the water jacket blocking the heater core and any other small aperture it can find, the heater matrix is part of a bypass system for the coolant this ensures you get heat in the cabin as soon as the engine starts to warm, the silicate will also jam open thermostats. Steve.

Hi VW electrics are way more simple from software to the actual wiring of the vehicle, not sure if its because VW are cheaper to buy so they spend as little as necessary to maximise profits, with Audi who seem a law unto themselves the designation Premium Brand has been seen as a licence to inflict the most complicated systems on the owner therefore negating any possibility of DIY on even the most basic level without special tools and diagnostics, the Volkswagen dealers are a mile apart from Audi I recently enquired about a part which I bought to see how much the chrome trim was that fitted to it, turns out the trim was more expensive than the part so they gave me the part number and suggested I looked on line, £45 V £95 from the dealer, thats proper customer care. Steve.

Have you looked underneath the wheel arch there should be a plastic access panel which you unscrew the fixing and pull out to gain access to the rear bulb housing cover. Steve.

Hi what sensor would that be, that looks like a lift pump housing, any description of where and which would be good. Steve.

Hi Volkswagens are good I now run a Passat as a cab, still having counselling for the five years that I ran an A6, you would never believe that both cars originate from the same group. Steve.

Well spotted Cliff I did not look at it for long enough, my mistake. Steve.

Hi an hour window on the change is as far as I would go when changing, see if you can find a mobile diagnostic specialist and explain your problem, chances are they will know a way around unlocking the can gateway, make sure the battery is fully charged, I have had your problem with OBD 11 but its always when its due a big fat update which they tend to do about twice every month so check that first. Steve.

Hi this problem is not peculiar to your vehicle or any brand for that matter Vauxhalls are famous for it, the problem lies with the system it runs water from the engine in tandem with oil going to the filter to cool the oil, the gaskets used are some sort of Nitrile based rubber and worse case scenario is water escaping in to the engine oil as if left it will cause premature component failure in the engine and will block any small oil gallery it comes across, its always a horrible job as they put it where you can't get at it easily necessitating removal of the exhaust manifold, good workshop policy is to renew the filter housing as often as not it warps when you take it off. Steve.

Hi did you code the new battery in when fitted, and was it any length of time before the change with the old unit flat, sounds like the Can gateway has thrown a hissy fit and shut itself down because at some point in the process it thinks its being stolen. Steve.

Hi NO you can't remove the sign permanently best to get it re gassed as soon as possible, this will involve them pressure testing the circuit , cheap it aint but its better than having to buy a new compressor ££££££. Steve.

Hi Dont go there anything over 6000k is normally a blue light or higher up a purple light which wont really give you what you want and will be like a magnet for any police patrols who will then start asking awkward questions probably involving a fine at some point. Steve.

Hi yes they do degrade over time and when they start to die completely they go pink, if yours are the original bulbs they are either 3200k or 4200k, you can upgrade to 5500k or 6000k with a very noticeable brighter light my preference would be 6000k as this is a sharp white light, look on a site for valley lighting, you may be well served changing the ballast units as well as they can also degrade. Steve.

Hi thats the low pressure cooler blocking, official code P200 trap bank 1 below threshold, that would have nothing to do with the update unless the update was to help introduce more Adblue in to the system with blocks the cooler and valve, its a very common problem on any ULTRA engine equipped with that system, if you look through the A6 C7 forum the topic is well subscribed. Stev

Hi I take it they didn't want to give up the codes. Steve.

Hi from about 2000 most cars produced have a PCV that separates oil/air its a pulse diaphragm which stops excessively large droplets of oil from being reintroduced in to the combustion process, they never quoted it as being fool proof thus it still introduces oil vapour hence the sludge, I actually made a catch system that bypassed this as it vented any gas via a filter, the car ran marginally better but then you get the scenario whereby you had to wash the filter once a month and empty the tank every couple of weeks, not ideal when running a taxi especially during the winter months. As for the technical information, when I did my research late 2019 I did a fair amount of archive which I have had to delete about a year after to free up some space for my parts system from memory most of it was from German VAG forums, never thought I would be called on to resurrect it though I have tried recently before it occurred to me that why was I doing this as it has no benefit to me as it no longer is of any concern therefore I came to the conclusion that this is all about trying to prove who knows what, who has the greater knowledge, judging by the qualifications and trade contacts you have I would think you would have far .better access to the data you require, but you have still not answered as to weather you think that even if you remove and delete various systems you can still replicate the same emissions standard as built, therefore I am happy to take a step back and considering I took my vehicle to over 270k using the as built system, so if you are not going to delete anything or change any parts its a bit of pointless exercise. Steve.

Hi Spartacus is correct on every level even the suggestion of using an old laptop the reasoning behind this is that an older laptop equipped with windows eleven and used solely for your diagnostic program will run much faster than if you had it on say a Mac with all your personal stuff on it plus uploading your VCDS is more straightforward, I have an old DELL Latitude which works really well, fortunately your car is pre 19 when all the SFD bull started so you will be amazed by what you can do. Steve.

Hi most likely culprit is a failing EGT sensor, you can only diagnose the with live data [scan whilst running] there are a multitude of variables such as DPF pressure sensors, did they give you the original code that instigated the cleaning process?. Steve.

Hi it would be very helpful to tell us what the error message says and even more helpful if the car is scanned and produces a fault code. Steve.

Hi yes the dynamics you state are correct but its not the EGR that blocks everything up but the addition of crankcase gasses which contain high levels of steam/engine oil vapour and its universally accepted engine oil is not a very combustion friendly medium due to the fact it maintains its molecular structure at high temperatures, the fact remains that if you spend hours researching this as I did on the net the pros and cons are all there for anyone to peruse, the manufacturers spend millions of Euros on development to meet the compliance required for emissions and in my opinion if you can live with this and fixing the things that go wrong you can still enjoy the longevity associated with the older models, the key factor is NOX1 reduction as if you take in to account the effect of nitric acid on the respiratory system you then have to ask the question is my enjoyment of my diesel potentially worth a life that is shortened by my vehicles modifications, there are lots of different opinions on what heat does and plenty of blogs on post remap turbo failures due to heat, this debate will rage on until the eventual demise of the Diesel engine in cars, it a bit like who is the true god Christ, Allah, or Jehovah and that ones been going on for hundreds of years with each side firm in the belief that they are right, last and not least in view of the development times and costs do you realistically believe you can delete all these items and still obtain the same results as the manufacturer?. Steve.

Hi if its proof you need there must be hundreds of posts on here the prime one being look through the C7 forum for a guy called Big Townz he had god knows how much mechanical work and remapping done to his engine, the end result total failure, in essence the whole idea behind Ultra technology was to have a Diesel engine that ran a lot cooler thus producing less Nox1, this was achieved by using a larger coolant radiator with the addition of a low pressure EGR system with its own cooler which operates from start up to cut down Nox emissions until the main EGR valve opens when the engine is up to temperature, there is a fine balance between both systems that are a key to keeping combustion temperatures within limits so producing less Nox the remaing Nox is felt with by the SCR which injects adblue as required to cope with any Nox increase therefore deleting the EGR and increasing the gas temperature by about 40% has a negative effect on the SCR which will over inject to try and compensate, the next stage is delete the adblue system which creates even more heat, it is well known that a hotter running diesel will perform better and give better MPG the problem with tis is that in production of the engine they found the composite of the metals used could be downgraded as for all intents and purposes the engine was never going to run temperatures at the upper level, this saved money, running at higher than manufacturers temps causes turbo failure and even in some cases valve failure which is well documented on the internet mostly on US and European sites, my opinion from ownership is that these engines are already running on the edge therefore why put more strain on them. Steve.

Hi that on the Mini was to allow for oil expansion so you did not get so depressed by the amount of oil it burnt you sold the car, my nieces MINI 1 about a litre a month, no leaks just burnt and this was at 60k. Steve.