Spark plugs and how to remove them, on the TSI 1.2 Polo

[veteran]

The performance of sparkplugs has improved decade-by-decade and generally these days I think it's true to say that they require little attention. I've educated myself about them over a good many years. But a change of vehicle, to a 2017-year CJZC-engined TSI 1.2 Polo, coupled with a desire to keep one or two spare plugs to hand, has demonstrated a good deal of lingering ignorance on my part. So I'm hoping someone here, experienced in installing and removing spark plugs on 6R/C Polos, can enlighten me over a few things.

I've one or two long (approx 65mm) sparkplug sockets - for 3/8" and 1/2" square drive - in amongst my armoury of tools, and on vehicles I've had in the past they've been sufficient for the task, but I've no idea at this stage whether any of them will be suitable for the factory-fitted plugs in my CJZC Polo engine. According to my research, the specific plugs for this Polo and engine are:

VAG p/no. 04E 905 601B or NGK p/no. PZKER7A8EGS

That appears to be my choice, as regards buying some spare ones. However, the NGK plugs appear to be quite scarce, so I'll probably end up buying the VAG ones from my local VW dealer.

Other than the actual plugs, I'm wanting to buy a long, thin-walled socket (preferably 1/2" sq drive) of the appropriate size, to remove them and to be able to inspect them as the years pass. On a modern engine such as this, the technique for accessing the plugs seems to be: (i) undo short bolt holding down coil pack on to cylinder head, (ii) use suitable pronged tool to extract coil pack, together with the plug's cylindrical shield, and (iii) insert a long, thin-walled socket into the recess, over the spark plug.

So, what size of socket should I be looking for? What's confusing is that I've seen sockets up for sale described as "16mm socket (10mm)" Errh? In this example, is the 16mm the nut size on the sparkplug (and therefore the required socket size), and the 10mm the sparkplug's thread size? Am I correct in assuming that the size for a sparkplug socket is always as measured across the flats on the hex nut?

And does anyone know for certain what the socket size will be for either of the two sparkplugs listed above? What minimum length of socket should I aim for, too?

[iichel]

A quick copy paste from the factory repair information:

Engine codes CJZC, CJZD
Firing order 1-3-4-2
Spark plugs
VW part number → Remark*) 04E 905 601
Electrode gap 0.70 ... 0.80 mm
Specified torque 22 Nm
Change interval →

---


Special tools and workshop equipment required

t Puller -T10530-
t Spark plug socket and extension -3122 B-
t Torque wrench -V.A.G 1331-

---

Renewing spark plugs, 1.2 l TSI engine
Removing

– Loosen hose clips -1- and -2- and remove air pipe.

– Disconnect electrical connector -2-.
– Remove bolt -1-.

– Push puller -T10530- as far as stop into hole in ignition coil -1-.
– Tighten knurled nut -2- in -direction of arrow-.

– Pull ignition coil on puller -T10530- in -direction of arrow- out of cylinder head cover.
Repeat step for all ignition coils with output stage.

Notet Observe installation position of ignition coils with output stage!
t Ensure that the cables are not kinked or damaged.
– Unscrew spark plugs using spark plug socket and extension -3122 B-.

Note
Observe disposal regulations!



Installing

Note
When installing new spark plugs, regrease ignition coils with output stage using silicone paste → ETKA.
The applicable silicone paste is stated in the ETKA along with the corresponding ignition coil and/or spark plug.

– Screw in new spark plugs and tighten them to specified torque using spark plug socket and extension -3122 B- → Anchor.
– Apply a thin bead of silicone paste on the circumference of the sealing hose of the ignition coil with output stage -arrow-.
– Align and insert all ignition coils with output stage one after another loosely into spark plug hole.
– Press ignition coils with output stage onto spark plugs evenly by hand (do not use any tools).

– Tighten bolt -1- of ignition coil with output stage to specified torque → Anchor.
– Reconnect electrical connector -2-.
Repeat step for all ignition coils with output stage.


– Fit air pipe.

– Fit hose clips -1- and -2-.

Specified torque Nm
Spark plugs in cylinder head 22
Bolt for ignition coil with output stage 8

[veteran]

First, a quick mention of the VAG no. for the sparkplug. According to what I found on nemiga, VW issued an updated version of that plug for the 1.2 TSI (as a B version) in 2016. So that's why I gave the new B no.

Reading the copied procedure you've given, I've of course no idea what VW's puller T10530 and sparkplug socket and extension 3122B look like in detail but it might well be that when VW workshops do this job they make use of, for pulling action, the hole left in the coilpack after the coilpack's securing bolt is removed; DIYers will more than likely use instead the pronged tool that's been commonly available for this, from online sources and from car accessory outlets here in the UK, locating it under the bulk of the coilpack.

Obviously, I wasn't aware that silicone paste is used where the pack joins to the shield/output stage, since this is normally out of sight. I suspect the grease is applied principally to aid thermal conduction but it might also prevent muck and dust from entering the recessed sparkplug hole. I'll have to ask about it when I buy the VAG sparkplugs. I do wonder, however, whether putting a 'consumable' like that anywhere near the top of the sparkplug recess is sensible, as when doing the removal job small fragments of it could drop down the recess and then fall into the cylinder when you remove the sparkplug.

[RUM4MO]

I think that you will find that VW Group has been using contact paste for years, I just wipe it off the original plug's top contact and smear it on the next one - and so on, also I think that all my cars over the past - though that copies text makes it sound like it is also being used to seal the output stage plug/socket from moisture ingress, I would thought that a contact "assister" would be used on the top terminal of the plugs and moisture barrier paste used at the plug/socket interface - though these plugs/sockets are chosen to seal correctly under normal under bonnet conditions.

Sparkplugs, I don't think that you need to worry about any changes in design having occurred that would mean a new length of spark plug socket is required - I've always tried to use a tubular socket with a magnetic end to hold the spark plug, it is a Laser Tools item that works well when removing spark plugs that are mounted deep in the cylinder head, no extension needed.

Availability of new spark plugs, I would think that it will be difficult to buy suitable plugs at this point in time, when I bought my wife a used Fiesta with a 1.6 Zetec engine, I also found the need to get hold of a set of new spark plugs, but as this engine type was still quite new to market and the service life of these plugs was 80>90K my local Ford dealer's parts department could not help me for a few months, the aftermarket outlets will only start to stock suitable plugs when the demand rises.

BTW, I stopped "holding" spare spark plugs over 20 years ago due to the fact that modern plugs work for a lot longer than older ones and/or they get treated a lot better by modern engines than older engines - I do though seem to store the old plugs for a few years - "just in case" !

Edit:- I've now looked for the coil extractor tool and see that all it does is allow you to use the through hole on the coil that is used to secure it - to expand the extractor tool and lock it to the coil's upper body, then use the tool to pull these coils up and out. So, like it says in some of the USA VW Group owner's forum, if you are strong enough and careful enough, these coils can be extracted without a tool. Though, £24 will let you buy a minimalist one to make life a bit easier.

[veteran]

Rum4mo,

Good tip about the paste. Thanks.

As for the VAG part no. for the sparkplug, I think you and iichel may have misunderstood why I drew attention to the B version. The latter is a minor refinement to the 04E 905 601, as far as I can gather. However, it's not anything that would affect its length or the size of socket required to remove it. The change was probably to its internal resistance. Apparently, with the original non-B sparkplug, there were complaints about 1.2 engines misfiring under certain conditions.

But actually on the subject of the dimensions of socket required to remove the plug, what would you estimate to be the minimum length required? More importantly, what should the size of the socket be, ie. the 'spanner size'? 14mm, 16mm, 19mm, 21mm?

And the silicone grease you've hitherto found on the junction of the coilpack/output stage, what colour was it? Was it clear? Black? (Loctite market silicone pastes for automotive applications, you know. A small tube of it would cost less than a tenner).

[RUM4MO]

The spark plug tubular socket that I tend to use on inline/straight engines, is a Laser Tools item with 10mm written on it - but it measures about 16mm AF, the plugs for the 6J Ibiza and B8 S4 have are 15.8mm across the flats and the threaded end of the plugs are all 13.79mm.

Also, I have checked up on the Bosch website and the data there includes the A/F size, which they confirm is still 16mm, which means that the tool I have must be Laser Tools Number 3682 - as to why it clearly has 10mm stamped on it I can't say!

I've also had a look under the bonnet of my wife's Polo and there does seem tom be plenty room to use that tool to remove its spark plugs - the end of that tool is 3/8" square drive though I'm sure that you will have adaptors if you need them.

The colour of the grease/paste, as far as I can remember it was clearish>yellowish>greenish - definitely not black - what lots of places sell is thread paste to give the aluminium cylinder head an easier life, I've tended to use that as well as it looks like VW Group do use something on the plug threads.

Edit:- up to now I've never ever noticed any silicon paste being used on the coil plug/socket areas, though if I do find some, I'll make sure that I add a touch more if it looks like it needs it.

The spark plug revision issue is probably not relevant as they will keep revising these items with time and sometimes it will just be due to a change in manufacturing method brought about by "progress".

Another Edit:- the suggested retail price for the Laser Tools coil extractor tool which is 6298 is a bit extreme - so I'd be heading off to ebay to get one of the cheaper versions and put up with any pain that these cheaper tools cause when you make contact with the exposed threaded end!

Yet Another Edit:- in the past, when dealing with spark plugs that are buried deep into the cylinder head, I've found that I've needed two spark plug sockets, one fitted with a protective rubber boot that grabs the socket and one without the protective boot - as I've ended up with the socket "stuck" onto the spark plug due to the rubber boot! I know professionals will have things like locking socket set extensions, but so far I have not bought any, which might be where the 250mm Laser Tools 16mm spark plug socket comes into its own?

[veteran]

Been doing lots of digging on the Web and have uncovered the following data for the OEM plug and the NGK one:

spanner size: 16mm
outer thread size: 12mm
thread length: 19mm
recommended electrode gap: 0.8mm
1K ohm internal resistor
'gasket seat' type seal

As of today's date, prices from e-retailers vary wildly, from around £7 per plug to as much as £29 per plug. Buying off the Internet means of course that you can't see the quality until you receive the goods, so it might be risky not buying from a dependable highstreet car accessories store or from a VW dealer, especially as there are so many counterfeit goods being sold over the Web these days. That's down to personal choice, I guess.

I've discovered that NGK introduced their PZKER7A8EGS for just a few Polo 1.2 TSI engines (including the CJZC) in April 2014, so this plug's been around for well over 3 years now. I suspect that VW themselves issued the 04E 905 601 somewhat later, and it might be that they got either NGK or Bosch to make them for them, just re-badging the plug. Some e-retailers describe the NGK one as a 'replacement for 04E 905 601' but whether that means that a change in technical spec has occurred or instead it's simply that the NGK one is an exact equivalent is anybody's guess.

OK, I now know the size of socket needed to fit and extract this sparkplug - 16mm. But I still don't know the optimum length of a 3/8" drive or 1/2" drive 16mm socket that'll be needed to comfortably perform the exercise.

[RUM4MO]

The Laser Tools socket I gave you the part number of is 250mm long.

VW Group will not be making any thing like spark plugs, they will outsource that and you will find that if you buy plugs from VW Group, they will carry VW AG and NGK markings on they, and will include the VW Group p/n on the metal shoulder along with "JAPAN", so no secrets there.

[veteran]

Rum4mo,

Our replies crossed.

My own past experience with sparkplugs echos yours.

Regarding the grease/paste, I might indulge, when the time comes, in some Loctite clear silicone paste. One of its principal applications is for automotive ignition systems.

As for the stuck rubber boot issue, there are sparkplug sockets made now that have magnetised ends. This apparently deals with the rubber boot problem. Also, with no rubber insert there's no risk of the rubber ever fragmenting and bits of it dropping down the hole and possibly into the cylinder. However, I personally think it's a good idea to still have a rubber insert because (a) you can usually use the insert on its own to start re-screwing the plug into the head (the age-old problem of sometimes getting the threads crossed; the rubber insert can act like a slipping clutch and prevent that crossing of the threads), and (b) it'll give a little bit of cushioning to the ceramic barrel of the sparkplug, should your tightening/loosening ever stray unduly from the vertical.

As for VW putting paste on to the plug's threads, I would think that very unlikely, as all sparkplug manufacturers warn never to apply any grease or other compounds on to the threads, as this markedly affects torque (you can easily end up over-tightening the plug, risking a cracked recess).

That aside, I'm not exactly sure where you're saying you've found the silicone paste when you've removed sparkplugs before on VW vehicles. I thought the paste has to be applied somewhere around where the coil assembly meets the outside of the sparkplug shield, but I might be completely wrong about that. Since silicone is an electrical insulator (but has excellent thermal conductivity), you'd want to keep it away from where the top electrode of the plug meets with the shield (inside the shield).

Sealey make an especially long 16mm sparkplug socket that's not hideously expensive. It's for a 3/8" drive and, as with your Laser one, is 250mm long. But I personally think that's a bit TOO long. See here:

https://www.amazon.co.uk/Sealey-AK6552- ... ley+AK6552

Incidentally, it's dawned on me why we see '10mm' enscribed on sockets that are clearly nothing like that size. 10mm is, near-enough, 3/8". The 10mm is therefore refering to the size of the square drive. But goodness knows why the manufacturer enscribes that, rather than the across-the-flats 'spanner size'. Maybe it's a manufacturing error and the socket gets sold off to the public cheaply?

[RUM4MO]

It is only contact grease I'd expect that I have found on the original factory fitted plugs - never on any cars that dealers have already replaced the plugs on though!

Using maybe anti seize paste on torqued items, yes not a good idea, though maybe at these low torques and with a bit of common sense it can be avoided if you apply the old "just tight" then add in a bit to compress the sealing washer, I've never had any trouble damaging the threads and it avoids some of that nasty crunching noises you get when removing a plug that was been in for the normal manufacturer's service life.

I can't think of where I bought my long Laser Tools plug socket, probably Toolacademy.com as they tend to be one of the cheaper tool outlets online.

[veteran]

Went out to the garage and had a much closer look at my coilpacks. I measured up a few things and observed with a strong LED torch.

From what I've read, it would appear that the shielding around the sparkplug, in the recess, is largely in the form of a rubber boot, though of course I wasn't able to see that in situ. What I was able to see - just - was a circular rubber seal, possibly part of that same boot, where the shield emerges from the recess. I guess it's all there to keep dust and debris out over the longer term. It may well be that that's why the boot and seal, together, are difficult to withdraw in this exercise. I saw no sign of any silicone paste. One thing's certain, though, and that's that any prong-shaped pulling tool (as suggested by Haynes for the pre-2014 Polos) is not going to be of any use on this sort of coilpack design, which is physically bigger than was before. Instead, it needs to be the VAG tool T10530, or an equivalent. I think if you were to try a cruder, more robust method for extracting the boot/shield/coilpack, such as levering with a screwdriver, you'd almost certainly permanently damage the coilpack.

But surprise, surprise, Laser Tools now sell their equivalent of the T10530. See here:

http://www.lasertools.co.uk/product/6298

Indeed, the Laser version can now be bought on Amazon and on eBay. It should be possible to pick one up for £30 - £40.

I wondered what the large arches in the tool were. They're of course for your cupped fingers. It might be called a puller but it's you who have to do the pulling. So whether using the tool actually gives much mechanical advantage is perhaps questionable, especially as the pulling is done only on one corner of the coilpack. I think you'd have to be careful still not to crack or distort the coilpack.

[RUM4MO]

As far as the Laser Tool is concerned, I mentioned that item in one of my postings to this thread, though maybe added it as an "edit".
The correct VW Group tool has a better "handle" on it, but I'd doubt if it is £|50 or £75 worth of "better", if VW Group consider this method as being safe even for service fitters to use in their branded dealerships, I'd reckon an average DIYer would also be able to safely get these coils out using that general type of tool.
For what it is worth, I removed the coils in my wife's old 2002 Polo twice to replace plugs and twice to replace faulty coils using a pair of screwdrivers and a lot of common sense - and they suffered nothing other than slight cosmetic damage.
What you need to understand is that these COP units have a long "pencil" type connector to reach way down to the sunk spark plugs, probably about 4 to 6 inches in old money, with a rubber gasket seal at the top of that "pencil" to seal against any nasties that might otherwise end up down that hole/bore. You will never see any signs of silicon paste there as it is only applied up inside the end of that "pencil" where the HT contact is, as you would expect, the pencil continues down beyond the HT contact point to shroud the nose of the plug.

I still think that with a degree of care, these latest coils could be removed by using two levers under the lower large square part of these coils - used diagonally opposite each other, and/or by pulling them up vertically using a strong hand and fingers.

Edit:- the Laser Tools version of the tool needed to extract the coils on my 2011 S4 is just "bracket" that slides over the coils and grips on the ribs provided for that - and it has a large ring on top of the bracket to get a strong finger through to lift them out - that worked okay for me with my smaller type of fingers.

[veteran]

I had noticed earlier that you'd mentioned that Lasertools made a suitable tool. What hadn't dawned on me, until I discovered it later myself, was that it was reckoned to be equivalent to the VAG T10530. But anyway, like you say, it isn't precisely the same as the VAG one. There's some sort of extra handle built into the top of the VAG one that the copied one doesn't have. I've wondered whether the extra bit is a mechanism that allows you to squeeze the grip rather than merely pulling it upward (it therefore providing some mechanical assistance).

Clearly, these tools are all quite expensive, so you need to be pretty sure they'll actually do the job before you buy. Otherwise, as you say, you might just as well unscrew the bolt and then just use your hands to pull the assembly upward and out of the recess. But with it being at the back of the engine compartment and not being able to get your fingers right underneath the coilpack, it'll be tricky to exact enough upward pulling force, whether you use a puller tool or not.

The copied tool is advertised as being suitable for use on late Golfs, Skodas and other models with series III engines, but nowhere is the Polo mentioned. The thing is that over the last few years - as with a number of components on these cars - VW has played around with different shapes and different methods of construction of the coilpacks, and I rather suspect that this copied tool may well fit on to some coilpacks but not to coilpacks on a different model of VW, or even a different year of the same model. If buying, it's a risk you have to take. We're even assuming that that bolt-hole is of the self same diameter on all the vehicles for which the copied tool is claimed to be usable.

On the matter of the sparkplugs, I've been looking into what Bosch make for the 1.2 TSI Polo. It transpires that their equivalent to the VAG one has the Bosch ref. no. 0 241 145 515. I've double-checked this with Bosch's online catalogue for this area of automotive ignition systems. In reality, it might be that the VAG one is simply a Bosch one rebadged. It's a double-platinum type, made to quite exacting standards, and therefore attracts a large price, typically £15 - £20 each. One of the cheaper prices in that range is offered by an Amazon seller. However that seller's situated in Latvia. I've nothing against Latvia or Latvians but it'd mean that if you were unfortunate in getting a faulty one, you'd have a lot of bother to send it back and get a replacement; it's not like going along to your local ECP. Incidentally, I've noticed that, for the NGK version, ECP's data on the sparkplug is wrong (wrong thread size). Again though, ECP want over £15 for the Bosch one, and around £19 for the NGK one.

[RUM4MO]

I think that you will be correct about the extra shaped part on the genuine VW coil extractor tool, plus it will avoid the palm of your hand trying to crush down on the nut for the expander bolt - some cheaper ones are even cruder and your palm would end up crushing down on to the exposed threaded end of the expander bolt. Obviously VW's tool supplier of choice had more money to spend at the design stage of this tool and came up with a more elegant solution that will be more comfortable for a service fitter to use regularly in a main dealer workshop.

I've made myself an NGK spark plug user especially with VW Group cars as it seems to be typically what VW and Audi use, SEAT and Skoda, for the same engines as VW use, tend to fit Bosch - for the reason that you have found - cost!

Typically I buy any NGK spark plugs I need from places like sparkplugs.co.uk etc, though as I've said earlier, if NOS VW Group spark plugs appear on ebay from a UK based "old stock" reseller, I buy from them - and even places like sparkplugs.co.uk etc sometime only sell the VW Group branded/boxed versions of some plugs when that marque is the main user of that version of plug.

While Latvia is just over the North Sea from us, and it seems like the parts pricing is "good for us" there, normally the shipping costs mess that idea up, I'd think that they would resolve any issue though, but again the buyer normally has to pay for any extra postage costs - being an etrader in ebay is a business for some people so they would not want to get bad press.

Edit:- going back to a comment you made some time ago, I think, as regards fake copies of parts, once I discovered Pagid and/or Textar brake pads being sold very very cheaply from Turkey - I looked into that out of curiosity and discovered that Pagid and/or Textar do have official factories in Turkey, but the Turkish government, no doubt with EU funding, also helps the setting up of "copy factories" for parts and they all get exported which is good for Turkey, but could be bad for the rest of the world!

[veteran]

Been exploring where it's possible to buy Bosch and NGK sparkplugs, for these latest 1.2 TSI engines.

Rum4mo, I think you'll find that, at the moment, sparkplugs.co.uk don't sell the NGK PZKER7A8EGS. Do bear in mind that this particular no. is the equivalent of the OEM 04E 905 601, which received a tweak a couple or more years ago. What I've found is that when searching around for a new set of plugs for a decent price the one thing you must double-check is that what you're buying is definitely for the engine in question. I've been exploring some german suppliers and, here and there, the recommended plug can depend on the engine details, eg. mine's a CJZC. Nowadays, it seems that plugs are absolutely tailored to specific engines and therefore don't necessarily get thrown under one umbrella, such as 'for VW 1.2 TSI'.

Other suppliers I've looked at are:

sparkplugsrus.com (Vega Racing Components, Braunston, Northants) NGK price £13.78 incl VAT each
gsparkplug.com (Greenspark Plug co., Middlewich, Cheshire) NGK £11.83 incl VAT each
autodoc.co.uk (part of Autodoc GmbH, Berlin) NGK £9.84 incl VAT each

These tend to charge quite a lot for delivery, typically £8 - £9. Autodoc also sells the Bosch one (241 145 515) for around 2 quid cheaper than the NGK.

Halfords don't do either one. I suppose if I were willing I could take a trip down to my local Halfords and ask them to order in for me either the NGK or Bosch, but I'm not sure now amenable Halfords would be to that. Also, it'd be a 4-way round trip. Trying to order either brand online from Halfords, for these particular nos., simply returns a blank result, as Halfords don't normally stock these.

As I think you've mentioned before, eBay's another source, though personally I'm not a great fan of buying from eBay (risk of fake or faulty goods).

Euro Car Parts are another possibility. Apparently (and I use the word advisedly), they sell both the Bosch and the NGK. However, they seem to come in plain boxes and the plugs are unmarked. Further, ECP has got the specification for the NGK one wrong, which doesn't, for me, engender much faith in ECP.

Obviously, if you're looking to make the best savings then, of the aforementioned, autodoc.co.uk would be a good source. Even so, for a set of four, you'll not have much change out of 50 quid by the time the delivery charge is added. Buying the OEM ones from the local VW dealer is still an option, of course. Sometimes, a dealer's price for a consumable such as this can be surprisingly reasonable, and of course you won't have a delivery charge to pay .......... or is that me just fantasizing?!

Edited on 21st Oct: I believe a number of retailers are now selling the Bosch one through Amazon. I think that before I or others rush to buy specifically either the NGK or the Bosch from any retailer, at least one of the existing VW-fitted sparkplugs should be removed from the engine, to see what's already there (unless you know already, of course). These days, with VW chopping and changing things on their cars almost every six months, it's sensible to double-check, for example, the design of the top connection on the sparkplug, to see how it mates with the EHT connection coming out of the coilpack/pencil shield. I see, for instance, that some sparkplug manufacturers have introduced a 'cupped' top connection. Whether that's something brand new I don't know. Although in principle the top connection should, for backward compatibility, be a standard sort of snap-on affair, manufacturers are constantly making small design changes to their plugs. What you wouldn't want to have happen is that you spend £40 - £50 on a set of plugs and then at some critical time in the future you go to fit them and suddenly discover that they're not quite the same design as the original and can't actually be used.