nta16

So what has changed from 20 January when the engine started and died a few seconds later to now when the car runs for 20 minutes and stops then restarts after 10-15 minutes - you are a little sparing with the information you're giving out. The stopping after 20 minutes and restarting after 10-15 minutes might be something to do with heat and environment, a fuelling thing possibly combined with with heat and environment, one, both, neither perhaps electrical. What happens the engine stops, what happens if you try to start the engine before 10-15 minutes? What are the makes of the new spark plugs and HT leads? These type of problem are not uncommon and can have lots of causes, some very simple so often overlooked.

Nickel is fine they are copper otherwise - "Copper spark plugs have bodies made of copper with center electrodes comprised of nickel alloy." "The majority of spark plugs feature a copper-core center electrode. Copper is an excellent conductor of electricity – better than any other type of material used in spark plugs – and also transfers heat faster. However, copper is soft and has a low melting point so it is always covered with a nickel alloy to protect it." - Champion Guide to spark plug materials - https://www.championautoparts.com/Parts-Matter/automotive-repair-and-maintenance/Spark-Plug-Materials.html Sorry that was a typo (well copy&paste) I meant K16TT. “Also, there is a myth that the fine-wire precious metal plugs should not be gapped. That is a false statement. You should always double-check the gap using a wire-style gapping tool. We do not recommend using the ‘coin’ style gapping tool because it can damage the fine wire tip.”

I can imagine copper plugs would be the best suited, but as I put before when you were testing the BKUR5ET-10 is that not at the same time as your coolant was too thick and before the last remapping, if so that could have had some influence on the results. The NGK plugs at least are factory set, and any three/four prong I imagine, to whatever is on the packaging but if they have been dropped or messed with (parts returned by customers) then perhaps they might be damaged or gap reduced. Have you never taken a part out of its packaging to realise that you were not the first to do so. Best to check all parts as soon as you get them so you have time to get replacements if needed rather than halfway through the job when the shops are shut. How about less is more - Denso K16PR-U or if you must IK16TT K16TT- https://www.denso-am.co.uk/products/automotive-aftermarket/ignition/spark-plugs/ My car does not have the fancy electronics yours has but I found going from the very basic NGK to the recommended Champion or NGK or superior NGK made no odds to the actual running that I could tell. I now buy the recommended NGK or the basic NGK if I see them at a good price. (I set them 0.003" (0.076mm) wider as that was best setting for my car when tested on the rolling road (dyno)).

Unlike many, generally I like cleaning products and additives but prevention is always better than cure. You look after your car so your need for this level of cleaning would be a lot less than with the average car and I think it's not the type of thing for many, including you, to worry about unless you already have the parts off the car. Taking the throttle body off the car would possibly give more access for more thorough cleaning but it's not something you would do often even in 22 years and your level of cleaning it on the car may be very sufficient anyway. Different cleaners are going to be good at removing different contaminants and to me it is doubtful you will get one cleaner that does a great job against all. As Thefeliciahacker has put petrol is a great cleaner for the engine already. Scotty has a different view on Sea Foam and has videos on spray inside cleaners, as with that Chris Fix I do not think you would see much improvement, a lot of the smoke is the cleaner itself. Ever since the 1960s the engine have had to burn rather than dump to atmosphere plenty of muck so bits of residue lying here and there will make little odds (as I see it, others may know more).

Wasn't this "running on" or "dieseling" in the last millennium when I was a young girl, but so much has changed since then, it used to be all fields around here . . .

In that case you need the plug type that was in when the remapping was done. It's not a change of brand if you had NGK BKUR5ET-10 at time of remapping. Different stores will offer a different range of plugs, based on their databases and the fact that the model of plug could be superseded by the manufacturers of the plugs. It is like tyres and other parts if a large vehicle manufacturer wants a very specific part to be made it will be because of volume. It may be, and I do not want to shatter anyone's believe or marque loyalty but often a tweak to a part like tyres or plugs is needed to compensate for little glitches of design and manufacture, er sorry I mean, improvements in design and manufacture of the vehicles. As for databases they are unreliable as they are merged and errors are copied and multiply with more merging, copying and copying in substitute plugs full cross reference listings. The computers and internet have accelerated and exasperated the problems as no one checks previous lists and just accepts them. You would need to go back to when your engine was first used in your model and see what each spark plug manufacture had listed for your model and year and even then accept that some may be more suitable or better than others. Sometimes you can find PDFs of parts manufacturers' or supplies' catalogues from that time which will list the part numbers, but they may have changed the part number or superseded the part. Then you must also consider the plug would be for what was considered suitable at that time for a new factory standard car running at that time with the petrol, oils, ect. of that time. It is a good base starting point for a factory standard car that may or may not be bettered now given today's circumstances and how the car is now. You may find you have to accept a reasonable level for what you expect in a spark plug for your car as your real aim is for a level of precision that is simply not available or realistic in plug selection and certainly not without computer program tuning perhaps with rolling road use and/or real world road use over a reasonable period of time to cover all types of your use of your car. Chances are standard plug or one move away from it will be as far as you can get, then there could be slight variance for better or not so good from different manufacturers.

As a simplified generalised answer, if the gap is too wide then yes you could get a misfire at higher revs. - (Champion) Consequences of Incorrect Spark Plug Gap - https://www.championautoparts.com/Technical/Tech-Tips/Spark-Plug-Gap-Tip.html 0.8mm to 1.0 is a big gap difference (0.0345" to 0.0394"). To sound like a stuck needle, you must also consider your car is remapped so a small gap increase depending on applicability of plug may possibly be good, or might not.

That would probably be as a commercial contract at the time, plus of course 21 years have passed and your car is not as factory. But at that time did you not have your problems with coolant and mapping - if you still have them I would try putting the BKUR5ET-10 back in now you are sorted. However it depends on what plugs were in when the mapping was last corrected, this is the thing with tuning if you make changes then you may have to change the tuning which is why it is best to tune to allow for the wide ranges of circumstances for driving on roads throughout the year rather than what looks best at any given time. I am not a big fan of looking at spark plug colourings, there are lots of variables and they need to be pulled at the relevant point otherwise subsequent use and actions alter the colouring. If you wanted you could perhaps got to NGK with BKR5EIX-11. I assume (always dangerous) you engine is in the AMG, AMH, AMJ group.

With engine oil (and filter) timely regular changes are important, as well as air filter and even perhaps fuel (I found clean 🤣 city diesel like V-Power left a cloud of silver grey instead of the usual black dense ****), as with computers GIGO for cars SISO. As there are correct oils there's also quality of oils but that's a whole new argument, and regular timely changes are still required. Most, quite rightly, usually drive diesels differently to petrols, using (much) lower revs, and more torque, which can add to the clogging up effect so I'd also look at cleaning stuff after the air intake like MAF and throttle body as this could make noticeable improvements generally and are often not done previously. Once you get used to driving the car as a diesel rather than petrol, with a serviced and clean engine, you will see very good real life mpg figures - disregarding any dash figures on any car, but perhaps particularly a VW product. 🤣

If all the plugs have the same (small incorrect) gap it's better than if the gaps vary on one or more of the plugs. Even though the plugs come pre-gapped it is best to check the gap as soon as you get them and return any that are wrong to the seller. If your car has been mapped then I do not know but very much doubt, if it is all programming, that the mapper/tuner would have widened the gap, you would have to ask to be sure. Possibly a platinum plug might foul up more, you would have to check this as your car is not standard - I assume you are not LPG too. Even the old-farts that have the same model of "classic" (over-priced and over-valued) car as mine prefer to run on NGK than Champion. Not that my car would run well on platinum or iridium but I prefer to use standard copper NGK and change them every two years as they are so in-expensive and so easy to get at.

Fair enough, my post was a bit like your app but it brought the desired result. Lemark is one of the brands (like Intermotor) that are owned by SMPE / SMP Europe / Standard Products Europe Limited, more UK/Europe quality than proper Japanese quality - but if they work great but don't expect the same accuracy and longevity of accuracy and life as the higher priced other makes. Your app and phone might, and I don't know I'm just going on other (non-diagnostic) apps I've seen mates use on their phones related to cars, be a bit slower at (can't think of the right word so I'll just put) updating the info from engine to screen than you'd ideally want so don't expect real-time accuracy necessarily. Or I might be wrong and your system is lightening fast. Then there's the computer program behind the app to consider how good it is, and perhaps rounding ups and downs, also how good the sensor is, a good few variables from sensor head to screen readout. I think of the free or low-priced tools like these as being the same as the modern made mechanical gauge in my car, as I tell my wife it's called a gauge and not an accurate, as long as the needles behave in their usual way things are as normal. If your car is now running well the exact displays on a screen don't matter too much. 😊

Have you checked the points gap hasn't closed up - you get spark to each plug? You have to be careful with fitting new modern made ignition parts as some can be crap. What did you clean the points with, what gap set? Could be hall sensor or its wiring if damaged particularly, unlikely to be coil usually as they last decades, but they can go wrong or perhaps contribute to other elements to cause an issue. More info is needed, photos or perhaps a video, I always start at the battery posts, a low battery or poor electrical connections will hinder and perhaps be enough to prevent starting or as on top of other issue(s) to prevent starting. Best to start at the beginning with the basics as your recent actions may or may not be related - but if new parts are fitted don't dismiss them just because they are new as they sometimes can be contributing to or sometimes even the cause of the problem(s). I don't know the details of your Fun only remember them when they were first sold.

Lifted from elsewhere - "The process for testing the sensors is simple: The sensor needs to exceed .8 volt and drop below .2 volt, and the transition from low to high and high to low should be quick. In most cases, a good snap throttle test will verify the sensor’s ability to achieve the .8 and .2 voltage limits." Sorry I've no idea about the c02 of 89.6 g/km and how it relates to tail pipe MoT test. If you've not used the car for a few weeks possibly worth check the battery charge as you don't want any embarrassing hassle getting the car to the MoT or upsetting the tester's mood. Good luck, let us know how you get on.

There you go, generosity in which is the least ugly lump of metal and paint, both all totally wrong in my opinion, as a person of little or none aesthete, visual, or otherwise of lumps of metal and paint. I'm not that asexual! Well not quite yet, well I don't think so, perhaps I am but even as a red-blooded youth I've never seen much to get excited about with cars, does that make me some sort of anti-carpervert? (lack of smiley).

Yeap, you can only blame their parents/guardians, grand parents, trade training and general greed and laziness. There are many good people in the world and some are mechanics, many often, as in all walks of life, until they are corrupted.

Presumably that's another number plate that is for show purposes and not for road use in the UK. Both cars look good to me - but I'm an old-fart . . . and not into girls-fashion, girl-effeminate fashion, effeminate fashion, male-effeminate fashion. repressed male-female fashion, pretend macho (really repressed effeminate ) fashion, macho fashion or even old-farts fashion - perhaps as a mate once said, I'm asexual. Can't it just be, whichever car, is to your taste or not? I sometimes feel well out of it here as my knees don't have to be set at different time-zones so as not to squash my 'brains'. I've got a cracking line (unoriginal joke) for thomasinaspin's photo but I don't want to offend anyone particularly if that's not thomas's grey car. 😁

I was just typing, but rum4mo has given much more instructional information to my guesses. Personally I am not adverse to spraying a good liquid lubricant like GT85 on one SUITABLE item at a time to see if that alters the sound. I have known it to take away the sound (and even not to return) but that was only luck, perhaps washing away grit/grime/crud and/or lubricating. My guesses were. - Alternator? A pulley? Compressor?

Many time times I've had others misunderstand my deadpan posts so I know humorous intention can be be misunderstood or not appreciated. On this occasion I didn't read it as banter, possibly the bit about girls and the OP's poster name (? I've no idea of the correct term avatar? poster name? member's name?). And it did bring a pile-on of some other less than generous responses. Perhaps the OP's response was also banter and I misunderstood that too, so difficult with just the written word to read, in person there are so many more cues and clues to pick up from. You've put your post was banter, I missed it, it wouldn't have worried me personally if it was addressed to me but against a first post (under 'Noman' at least) to me it seemed a bit harsh. I wonder if Noman will now to improve their response. ETA: I personally dislike ego plates and those spaced incorrectly and B&W plates on those that would generally not had them when the vehicle was new - but luckily I'm not in the Police. 😅

All a bit harsh and lots of assumptions being made. Some people must be extremely crumbly if they don't know some girls not only like these sort of cars they drive them. If the car is being used on the road with an incorrectly spaced number plate that is wrong but so are many others, often ego plates on ego cars and vans owned by those old enough to know better. Not a good response - try again with a bit more info about the car and yourself - this is a forum not like FB or Twitter with short hit 'n' run posts, that post is like one you'd get from a 12-year-old troll.

Doesn't matter now but your vacuum gauge installation didn't sound right, and usually just making good non-leaking seal to all connections. The mechanic was trying it on by the sound of it, at worse you just remove the gauge piping and blank off or seal off or renew hose. Seems there are rip-off mechanics everywhere. I totally agree and owners forget the margins might be shaved thin which might be ok until you need the wider margins from something going wrong, or from wear or faults or very adverse conditions.

I did put less important, it's a matter of priorities. I know all about cars that become static roadside ornaments, I've not only got the t-shirt I paid for the design and manufacturer of it, which is why I believe in preventative checking and timely regular servicing, maintenance and repairs to the whole vehicle, most important with a car that is new and unknown to you. The engine is lower down the priority list of checking and servicing, maintenance and repairs particularly on a vehicle new to you. Many of the checks can initially be visual, you don't strip down a loan, hire or courtesy vehicle before you drive it but as you are responsible as the driver you would check it over (if only to save hassle and arguments later about its condition). As many prove by doing so, you can drive a vehicle with an engine that isn't running fully well or maintained well, it will get you there and back again many times and with safety. When you go to get in or check a vehicle your first thoughts should not be I must check the engine (oil) it should be brakes then steering, etc., stopping and controlling the vehicle is more important than starting and running. If the car won't start generally you and others are safer than if it won't stop. And yes the engine has effect on control of the vehicle but it's a matter of priority in the checks, if the brakes, steering, suspension (all three include tyres) are faulty then you may not be driving the vehicle so the engine condition is of little importance, a matter of priority. You want the car to brake, steer, handle well and have all necessary safety eclectic items working well before having the engine running in best condition, it's a matter of priority - the engine is important just less so than other things with the car .

You can get a leads or adapters for OBD and other systems, it is surprising how many different system there were/are, as always each group of manufacturers doing their own thing. The problem would be getting the various parts to work with each other if they are not part of the same kit. With the better scan tools you can either do live data and have a second person watch or you can record the live data as the driver to playback and interrogate later. With older cars the programs particularly need to be kept up to date as it is the users' feedback that improves the scan tool's programs as my guess would the car manufacturer's were not allowing the programs to slip into the hands of the Chinese, the top systems seem to be from China with very similar looking hardware with the user programming differentiating the different brand makes. With modern cars particularly but it was also with older cars, some lazy mechanics only want to play with toys and overcomplicate matters to make them look clever or so they can charge more, it's like plugging in a load of diagnostics to tell some one their battery is flat or dead or that they have allowed the fuel tank to fully empty. You have your TC-6 will all the programs to sensors in the old days it would have just been a vacuum gauge to tell you the engine's health and have you driving efficiently and economically. You want to think yourself luck that you have an earlier VW Skoda before VW decided to really over complicate the computer programs and make them invasive to each other and the operation of the vehicles probably partly just for the sake of of running away with the technology but as has been proven to also be able to control and fiddle things. I would guess that the programs were being developed for ever strict fuel economy and emission with ever diminishing return on the very ancient technology that is the internal combustion engine but also for safety regulations and marketing but also with an eye to self-driving cars to test out systems in real world situations. This has meant German cars in particular having the vehicle systems so interdependent that there are so many variations to any problems that arise that they even beat the manufacturers agents.

Always a problem with actually doing this sort of work but it would probably be more surprising if you do not find anything after 21 years of use but it does not mean it has to be bad and clearing it out probably helps a little. Do not forget it is a 'lifetime fill' so you are doing more than most owners would. I would guess there are many older cars still on the factory oil. I doubt you will notice much if any change but you will have boosted and prolonged protection I would not be surprised if the fresh oil soon discoloured a bit but that is nothing to worry about as it is only the oil doing its job and holding muck in suspension.

Sorry I don't know, Hella to me are lights, if it's working then that a good start, never just go by brand name even ones you think might be good or often fitted to the car and it might just be a label on a product made elsewhere, you can ask on here before buying. Always buy from a reputable source though unless you like gambling. Don't worry I'm sure someone will say Hella is fine. Possibly you might need to clear error codes or drive the car more for it to settle or it might just be the gauge, if the cabin is getting hot that is a good sign and probably a sign that the thermostat isn't at least stuck open at least, there are other ways to check the thermostat without removing it but as you have a scan tool you might as well wait for that. With scan tools do bear in mind the error codes often only give you a starting place for further diagnostics not the solution and immediately which part to change to resolve the issue. Also readings on the scan tool can be off sensors which may or may not be fully functioning and accurate, and it's just computer programs, you can know more than it and sooner often. The car may not show error codes but still be faulty and you realise this, we have senses, 7 (apparently), and a brain, often these are needed in conjunction with a scan tool or can be better or detect better/sooner than a scan tool. As the car is new to you take the time to not only change things like filters but to also do, if required, a bit of clearing out and/or cleaning inside the housing and inlet (outlet probably a waste of time on a diesel). Always allow plenty of time and don't be in a rush, best to do the jobs when the shops and motor factors are still open. Great that you are taking on servicing but do bear in mind the engine is one of the less important components on the car more priority should be given to checking, and if required servicing/maintaining/repair, the important component/parts/systems like brakes, steering, suspension, (all three include tyres) lights and visibility and safety electrics. As has been put no one is born knowing, we all had to learn for a first time even those that now know a lot. That doesn't included me, I am not a mechanic or expert in anything, what very little I might have known I forgot or repeatedly forget but I do have decades of experience of car ownership (and the English motor trade). Giving as much information as you can, especially with your opening thread, which may mean repeating some stuff from previous threads, helps those that respond. Good clear photos can often help no end - (plea from me, please hold the phone horizontally where appropriate as this gets more into the photo frame generally). If you are going to do a lot of short journeys (not a good ideal for a car and particularly modern diesels) keep a check on the car battery and how much charge it has, starting the car is just one of its jobs. I much prefer prevention to cure and unusually for someone on a car forum I loathe doing anything but driving a car so I think it is a good idea to put a bit more effort in at the start of ownership and during regular servicing and maintenance to avoid doing more work later when it's less convenient or takes you away anything more enjoyable. Let us know how you get on.

If you can put a good few few drops out of the syringe into a set of small clear contains until you are sure you have got to the dirtiest part and before you flush with clean the dirtiest sample will probably tell you the most and you can dispose of the rest. It is any solid bits that will be of most interest if there are any, as you expect deterioration of the oil and its additives and dye and for it to pick up some contamination.