Scirocco Central

24S4 - There is a small sticker, on the boot floor on the left rear side (under the carpet cover). It will have written on it 24S4 and a dealers stamp if they did as instructed.
There can be other update stickers there if for instance it has had replacement boot struts due to rusting mounting plate anchorages & screws on 2008/early 2009 Sciroccos.

Otherwise the absolute checks without visiting the dealers.

Manual Gearboxes:
The gear indicator is in the dash central MFD. Map standard is checked like the DSG below except the map is G5859 or 0888 or latest 1676 (end of August 2011).

DSG:
Needs VCDS go into the Engine 01 controller and look at the ECU software version as here.
G5860 or 8913 or 9256 or latest (17 Sept 2011) is 9660 are the 24S4 maps, the latter three taking care of a misfire that happens at about 1 to 2 minutes from cold start, depending your driving style and how fast warm-up is progressing. This one is specifically when the engine coolant temp is around 35'C which can't be read of the dash dial. I trapped it using the VCDS logging when a misfire happened.

ETA: 1676 & 9256 also introduced a correction for the lack of enough engine heat to drive the heating system, already available of the 1.4TSi 122PS since mid year.

C.

I put my late 2009 1.4 160ps DSG into my local dealer because of a hesitancy when I was accelerating, it didn't seem much but I though I would get it checked.
This was last Wednesday, so I go to collect the car because they thought it was an mapping problem and they tell me it needs new injectors, they lend me a brand new 1.6 diesel Golf.
Friday they ring me and say that the cylinder head needs to come off.
Today I ring them wondering where the car is, they say that the Head is back on but the car still has low compression (first I'd heard of this).
They say that there is a problem with the bottom end and will call me.
I will let you know what happens but what do you lads and lasses think the answer will be?
Rusty

Had a misfire issue when the car was a month old, 1000 miles on the clock, engine management light flickering when accelerating. Turned out the spark plugs were frazzled. completely. No idea why, I hadn't stomped the car and i'm not a racer or anything, just one of those things i guess.

Changed the spark plug gap again last weekend, after some thought.

At the service I did in late May, a very slight misfire (no dash lights) was found to be a slightly wider gapped plug in one cylinder. It was gapped at 0.84mm (33 thou) while the others were set to 0.79mm (31 thou.) the previous time in Spetember 2010. (Don't know how I managed to set the gap (0.84) incorrectly last time. ) Changed to 0.79mm and the misfiring cylinder I could detect dissappeared. So on the basis 0.84mm was where the engine was still misfiring very slightly and 0.79mm being OK, I decided to shorten the plug gaps to 0.74mm (29 thou) at the weekend. On start up with the Scirocco just on the drive, the cold engine was different again in the EGR mode.

More interestingly driving around the last 4 days, there has been marked improvements again ........

Starts better. The dieselling noise in the rear exhaust area is quieter.
Less exhaust/engine noise generally.
Pick up from 0mph is very smooth now.
DSG creep mode very smooth and positive.
DSG 1st to 2nd gear change was originally a lurch, shortening the gap improved it the first time but this new setting, its totally gone.
DSG is now holding a higher gear at low rpm and so the engine is ticking over when pootling along.
DSG boom in the rear exhaust when warming up has almost gone.
Hill Hold is more positive with the DSG clutches engagement.
Runs even smoother while driving.
Performance hasn't, at face value, been affected at any speed or engine rpm.
No VCDS faults or engine temperature issues. All working normally.

Another noticable level of change all round. For only another 2 thou change in the plug gap.

So it appears the plug gap is better set at 0.74mm - 0.79mm (29thou - 31thou).

This is a little way from the factory fitted plugs (& spares) gap setting range of 0.90mm - 0.92mm (35.5thou - 36.6thou) that NGK supply to VW. And below VW's workshop manual specification of 0.80mm - 0.90mm (31.5thou - 35.5thou).

In effect, the plugs as fitted at the factory, could be considered to been worn out when new! As the upper gap limit appears to be around 0.80mm to 0.84mm when misfiring in my engine starts to happen very, very mildly.

(NB: You have to be very careful re-gapping fine wire spark plugs that have very small diameter platinum or iridium alloy electrodes. Feeler gauges or wire gauges should be used with gentle care when testing the gap by comparing with the feeler gauge. Otherwise the central electrode tip will be damaged.).

C.

Seems weird that VW would have the gap all wrong. Shouldn't there be misfires in all engines, if the standard plugs are over the specification and the correct value is under the specified gap range?

RoccoScientist wrote:Seems weird that VW would have the gap all wrong.

Perhaps someone in VW Purchasing Dept. hasn't told NGK that the gap of the supplied plugs should be 0.80mm when new, not 0.90+ mm. They won't have time to tweak the gap on the production line. Fit and move to the next engine unit build.

I also looked through the workshop manuals today. Technicians are not specifically instructed to check and adjust the plug gap when fitting replacement new or existing plugs. Many modern multi-ground electrode spark plugs are not gap checked due to design or the path the ignition spark takes. So the old habit of gapping a plug with feeler gauges has most likely not crossed their mind when fitting the plugs or carrying out engine checks.

RoccoScientist wrote:Shouldn't there be misfires in all engines, if the standard plugs are over the specification and the correct value is under the specified gap range?

Well yes, that logic does follow......

But I think the murmuring misfiring is not likely to be noticed by most owners at the factory supplied plug gap setting of 0.90+mm.

What drove me to investigate the plugs last July - September 2010 was that the diagnostics and coil pack swapping were not making any sense. Move the offending coil pack to another cylinder and the misfire fault in the ECU went to another cylinder which was not the original or where the "faulty" Coil Pack had been changed to!

So I went back to basics and pulled the spark plugs to initially see what condition they were in along with the piston crowns and cylinders. And of course basic habit was to clean and check the plug gaps. The gap surprised me against the VW Workshop manual setting range, as it did on the spare plugs I had to hand.

What effect followed didn't surprise me after re-gapping to 0.79mm (0.8mm) as it was the equivalent of adjusting/replacing worn plugs many years ago when only single ground electrode plugs were available generally. The surprise for me is the additional reduction from 0.79mm to 0.74mm gap and what has further happened to the drivability of the Scirocco. Usually if one drops below the VW spec lower limit, the ignition performance drops off again.

From the horse’s mouth.................

NGK Spark Plug Company wrote: Since the gap size has a direct affect on the spark plug's tip temperature and on the voltage necessary to ionize (light) the air/fuel mixture, careful attention is required. While it is a popular misconception that plugs are pre-gapped from the factory, the fact remains that the gap must be adjusted for the vehicle that the spark plug is intended for. Those with modified engines must remember that a modified engine with higher compression or forced induction will typically require a smaller gap settings (to ensure ignitability) in these denser air/fuel mixtures. As a rule, the more power you are making, the smaller the gap you will need.

I checked the 1.4TSi 122PS engine plugs today. Same spark plugs (Part No. 101 905 626). Gap setting: 0.80mm to 0.90mm.
But on the 1.4TSi 160PS, it has the maximum boost increased from 1.8bar to 2.0bar and a supercharger boost fills the pressure gap below about 3,500 rpm to give an almost constant 2.0 bar boost when the engine is under load. Yet the plug gap has not been closed down. Has VW made an oversight??. And 0.74mm – ish is the lower gapping set point.
ETA: 03C 905 601A has superceded (30.09.11) VW previous part 101 905 626 on the 1.4TSi 160PS only.
ETA2: VW have officially recognised the 1.4TSi 160PS spark plug gap at 0.7mm . Revised plug part number: (again!) 03C 905 601B.

NGK Spark Plug Company wrote: A spark plug's voltage requirement is directly proportionate to the gap size. The larger the gap, the more voltage is needed to bridge the gap. Most experienced tuners know that opening gaps up to present a larger spark to the air/fuel mixture maximizes burn efficiency. It is for this reason that most racers add high power ignition systems. The added power allows them to open the gap yet still provide a strong spark.

Nor have VW increased the power of the coil packs of the 160PS over the 122PS. Both engines use the same Coil Pack part. Could be the pack is intended for 160PS.

------------------------------

The failure in the 1.4TSi 160PS when it started in Australia back in July 2009 came out of the blue to the owners. They were driving around with what they thought was a good engine. Next minute.... bang, dash warning lights on and an engine karput. These owners (& others in Germany) didn't sense a continually misfire over a number of months as to most, the 1.4 runs quite "normally".

If these owners (& others) didn't/(don't) sense a chronic long-term detonation problem (murmuring misfire) until the dash warning lights or terminal end, who knows how many are experiencing " murmuring" misfires over a long duration (not a juddering, physical shaking that is obvious). Perhaps I am sensitive to an engine and recognise when it is not in tip-top running order.

The chronic long-term detonation problem (murmuring misfire) may or may not lead to the piston failure through lack of oil due to unburnt fuel washing the cylinder bores and trapping the piston rings which leads to pistons fracturing. That is the mechanism of the failures.

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The faulty coil packs & injectors batches have not always been on the failing engines. These faulty batches of components can also lead to the same failure through cylinder bore washing occurring, as misfiring also occurs with these faulty components. So that confuses the picture to most about the engine failures.

C.

Okay, now I'm going to get paranoid and I wouldn't recoginze a misfire even if it bit me in the *ss. Any chance you'd like to come to Finland and testdrive my 122 PS Scirocco? ;D

Seriously though, I'm probably going to try and test the plug thing at some point and just the possibility that the engine would run smoother in the EGR mode would be reason enough. The whole EGR mode thing has bugged me for a while now, since it only happens when it's warm outside, the car sounds like an old Opel Kadett during it and if I don't wait until it's finished (might take about 45 s), the engine will not pull evenly for the first hundred meters or so. I even did a small test during the summer where I put the gear to neutral and tried to hold the rpm's at 2000 while the EGR mode was on. The rpm needle bounced around the 2000 rpm, I heard small "pops" in the cat and after a small while (while I was trying to figure out where the "pops" were coming from) a yellow warning light lit up and the Star-stop-system malfunctioned. What I've gathered from the dealer's and importer's comments, is that in some conditions (warm summer air) the engine runs on a higher fuel-to-air ratio to warm up the cat, but the problem in my experience is it doesn't seem to know how to adjust the ratio if you try to actually drive the car, although the symptons do vary a bit from car to car and engine to engine (all TSI engines including 1.2 TSI, 1.4 TSI, 1.8 TSI and 2.0 TSI seem to bee affected to some degree). One 122 PS Golf owner even had the motor stalling during the EGR if he didn't give the car some gas during start up. But I'm going off a tangent here... The thing I'm interested in is: Would changing the gap in your opinion be so beneficial even for the 122 PS engine that it's worth paying for? Also, considering that I might remap the engine, should I go for a value of about 0.80 mm or less?

RoccoScientist wrote:Okay, now I'm going to get paranoid and I wouldn't recoginze a misfire even if it bit me in the *ss.

You shouldn't! It takes a very fine touch

RoccoScientist wrote:Any chance you'd like to come to Finland and test drive my 122 PS Scirocco? ;D

lol. I've had two call outs this week already. I'll have to start an appointments book

RoccoScientist wrote:Seriously though, I'm probably going to try and test the plug thing at some point and just the possibility that the engine would run smoother in the EGR mode would be reason enough. The whole EGR mode thing has bugged me for a while now, since it only happens when it's warm outside, the car sounds like an old Opel Kadett during it and if I don't wait until it's finished (might take about 45 s), the engine will not pull evenly for the first hundred meters or so.

I even did a small test during the summer where I put the gear to neutral and tried to hold the rpm's at 2000 while the EGR mode was on. The rpm needle bounced around the 2000 rpm, I heard small "pops" in the cat and after a small while (while I was trying to figure out where the "pops" were coming from) a yellow warning light lit up and the Star-stop-system malfunctioned. What I've gathered from the dealer's and importer's comments, is that in some conditions (warm summer air) the engine runs on a higher fuel-to-air ratio to warm up the cat, but the problem in my experience is it doesn't seem to know how to adjust the ratio.

If you try to actually drive the car, although the symptons do vary a bit from car to car and engine to engine (all TSI engines including 1.2 TSI, 1.4 TSI, 1.8 TSI and 2.0 TSI seem to bee affected to some degree). One 122 PS Golf owner even had the motor stalling during the EGR if he didn't give the car some gas during start up

The Coil Pack pulling tool is still the same for the 122PS engine as I have shown in my Scirocco Service topic link, ie. tool number T10094A which a dealer will order (UK price: £29 + VAT). It also covers the smaller engines in the 1.2TSi range, so may be you guys can share-buy one to hand around. I would not recommend levering out the coil packs with a screw driver or otherwise as the electronics in the top of the coil pack could be damaged. The coil packs are, on first removal, very stiff to move due to fit and the protective grease (damp protection). It takes a fair amount of effort with the correct extraction tool.

Something sounds odd with the warm-up and you cannot drive. The 160PS during the first 15 to 75 seconds (depending upon outside temperatures) isolates the supercharger by opening the supercharger boost control flap (full dump) and any engine acceleration is performed with what is available from the turbo alone. In the temperature range -20'C to +28'C I have driven from a cold start, the engine is flawless, and power isn't down very much that one would be concerned. Slightly different set-up but I wouldn't expect what you are describing.

The 122PS has had engine ECU updates as late as Wk14 (03.04.11) this year which appear to tweaking out misfire problems. (Updates also change the engine ECU to give better heating output for the cabin.) If you check here with VCDS for ECU software version, it should be a four digit number 9*** to have the latest. If I have the ECU part number from the same VCDS screen ie. where it shows in the link 03C 906 027BA, it should be 03C 906 016nn where nn is a double letter code, I can tell you which specific version number is the latest in the 9*** series.

RoccoScientist wrote:But I'm going off a tangent here... The thing I'm interested in is: Would changing the gap in your opinion be so beneficial even for the 122 PS engine that it's worth paying for? Also, considering that I might remap the engine, should I go for a value of about 0.80 mm or less?

(Tangent = split topic if need be.)
As the plugs are the same part, I think when you take them out you will find them to be gapped at 0.90mm - 0.92mm. That gap should be set to 0.80mm and there should be some noticeable effects I have described. Mapping – another ball game, but unless boost level is changed, then plug gap should be the same. Cold start maybe not, that is something else which other 122PS Scirocco owners will have to comment on in UK or other countries as an independent view away from Finland's climate.

C.

MY10 DSG7
done 12000km
never missed a beat

Great question, anybody with knowledge on this matter?

Thanks!

Took a look at the spark plugs again today after gapping them to 0.74mm (29thou) a couple of weeks ago. Yesterday, the Scirocco had a 2 hour drive on the motorway as well as the urban driving it has been having.

The plugs were clean and the colour one would expect from a normal running engine. The red scorching areas seen previously, when set to 0.92mm (36thou), are now absent.

(NB: You have to be very careful re-gapping fine wire spark plugs that have very small diameter platinum or iridium alloy electrodes. Feeler gauges or wire gauges should be used with gentle care when testing the gap by comparing with the feeler gauge. Otherwise the central electrode tip will be damaged.).
The scorching areas on the piston crowns have also gone. It was noticable that the oil was showing about 2'C lower for the same air temperature.

Given the engine ECU map (VW's) has changed from G4009 to G5859 (24s4) and the plug gap at 0.74mm, now happy the engine is running correctly.

C.

Sorry for the delayed reply, RW1. I had asked the place where I've had my car serviced to check the gaps on the plugs they're using. Just found out today, that NGK's have (according to them) a gap of 0.9 mm while Bosch (which they also use, but which is not available at the moment) has a gap of 0.8 mm. So, a weird discrepancy in the NGK gap, although it's still at the limit which means that it'll go beyond the specified value the second it starts to wear. I might have the plugs changed and regapped to 0.8 mm as I'm taking the car to them next week to have a BSR cat back installed.

RW1 wrote:Something sounds odd with the warm-up and you cannot drive. The 160PS during the first 15 to 75 seconds (depending upon outside temperatures) isolates the supercharger by opening the supercharger boost control flap (full dump) and any engine acceleration is performed with what is available from the turbo alone. In the temperature range -20'C to +28'C I have driven from a cold start, the engine is flawless, and power isn't down very much that one would be concerned. Slightly different set-up but I wouldn't expect what you are describing.

The oddness doesn't stop there, since the whole "EGR mode" only happens when it's warm outside (over 15 C) and the car has stood still for several hours. The warmer it is, the higher the odds that it will happen at startup - during the warmest period of summer it happened every time I left for work and every time I went home. Anyways, this was more of a side note.

The 122PS has had engine ECU updates as late as Wk14 (03.04.11) this year which appear to tweaking out misfire problems. (Updates also change the engine ECU to give better heating output for the cabin.) If you check here with VCDS for ECU software version, it should be a four digit number 9*** to have the latest. If I have the ECU part number from the same VCDS screen ie. where it shows in the link 03C 906 027BA, it should be 03C 906 016nn where nn is a double letter code, I can tell you which specific version number is the latest in the 9*** series.

Damn. I forgot to check this as we switched the XDS on. I'll try to remember this if we poke around with the VCDS in the near future.

does anyone know when the factory software update to resolve the misfire from cold was released? my 1.4 does it intermittently and I was thinking of getting a remap, so I want would like to get this installed first.]
cheers

Just got my 1.4 160 two week ago , done 800 mile and no problems , defo best car ive had to date !
The car is so smooth and handles amazing, so far so good ! although i have noticed a slight rattle whe revving when i have the stereo turned off.
Might take it into dealer to see if they can see what it is , i love it just wish id of got some mats ! Especially in this weather :/

I have a 2011 1.4tsi built in January 2011 that I picked up last week of Feb, I have had the misfire a couple of times, but not that was early in the summer and not since, with regards to spark plug gap, do you think that mine needs changing? From reading through the great technical post above, it seems that mine does not need a ECU software update as its running the 24s4, is this correct?

thanks for the help

diaz101 wrote:does anyone know when the factory software update to resolve the misfire from cold was released? my 1.4 does it intermittently and I was thinking of getting a remap, so I want would like to get this installed first.]
cheers

RW1 wrote:VW have now upgraded the maps to compensate for the 35’C stutter misfire in dry air during warm-up. Those maps were introduced in Dec''2010 as G0888(M.)/G8913(DSG) and have become the revised 24S4 installed ECU map standard.

Wk48/2010 onwards available.
Note the "dry air" comment. By dry, less than 20% humidity and.... the outside air temperature has to be up at 20'C plus. Lasts briefly for about 5 - 10 seconds as the engine coolant temperature passes through 35'C.
About halfway down this post the release is dicussed.

There have been other problems with cold start warm ups, which are posted on here. eg.
http://www.sciroccocentral.co.uk/forum/ ... art#p61527" onclick="window.open(this.href);return false;
http://www.sciroccocentral.co.uk/forum/ ... art#p54066" onclick="window.open(this.href);return false;

You would be better getting it diagnosed first as it may still be there when you re-map.

C.

diaz101 wrote:I have a 2011 1.4tsi built in January 2011 that I picked up last week of Feb, I have had the misfire a couple of times, but not that was early in the summer and not since,

Yes that could be the 35'C dry air problem at +20'C

diaz101 wrote:with regards to spark plug gap, do you think that mine needs changing? From reading through the great technical post above, it seems that mine does not need a ECU software update as its running the 24s4, is this correct?

Access to VCDS?? Post up the Engine ECU screen that follows selection of 01- Engine or post up the AutoScan section for Controller 01 (Address 01). Thats the only way (unless you go to the dealers) you can tell that 0888/8913 or 1676/9256/9660 VW map is installed which contains the rectifcation released in Wk48/2010.

24s4 is on its third issue as part of updates as the software for other reasons moves on. Best explained as this....

Wk39/2010 - "24s4 Issue 1" Work shop campaign released in UK/Europe as G5859 M./G5860 DSG (no 35'C warm-up correction).
....................................{Australian release May 2010.}

Wk48/2010 - "24s4 Issue 2" Incorporates 24s4 issue1 and 35'C warm-up misfire in dry air (less then 20% humidity) above 20'C
....................................Released as 0888 M./8913 DSG.

Wk35/2011 - "24s4 Issue 3" Incorporates 24s4 issue 1 & 2 and poor cabin heating performance/engine does not get warm,
....................................manual gearbox /clutch jerking.
....................................Released as 1676 M./9256 DSG.

Wk37/2011 - "24s4 Issue 3a DSG only" Incorporates 24s4 issue 1, 2 & 3 and another tweak for engine warm-up misfire at 35'C coolant
................................................temperature.
................................................Released as 9660 DSG only.


I initially changed my spark plug gaps in September 2010. They didn't load map G9660 today while at the dealers for a serivce, still at G5860. Still running without the 35'C coolant temp correction and no warm-up misfires since. Not a hint of the warm up misfire this year despite identical conditions where it should have happened. The same plugs as originally fitted at the factory.
(Note the comment! About adjusting & re-gapping fine wire spark plugs!)

C.

Thanks very much for the info, I have a mate with a workshop so will get the car checked over before I get the remap

My 160 arrives in a week or so and I'm excited, but nervous at the same time

Finally got hold of the 1.4TSi 160PS revised spark plug listed as a part on ETKA since 28th September - 03C 905 601A.

03C 905 601A is a NGK plug. Its like the original, has a Laser Platinum Fine Wire plug with crystals of Platinum on the central electrode tip to provide long service life. It appears to be the same plug but there is not NGK part number on the rim, just VW's like the original 101 905 626 plug. The length of the insulator and electrodes are identical suggesting its the same heat setting. But one diffference that I can see....... its preset to 0.8mm (31thou-ish), not 0.9mm.
Always worth a try but the plugs ain't cheap (£53.20 in UK for a set of 4) and resetting the gap of the originals has to be carefully done because of the narrow tip of the centre electrode and possible damage and possible damage to the longlife crystals on the tip.

As you are not really meant to adjust fine wire plugs, VW look as though they have revised the gap for the CAVD engine code, the 1.4TSi 160PS version. This means the factory and dealers can fit without any pre-setting. When replacing at the dealers, they don't do any gap setting. That has been confirmed last week.

So that confirms the original setting I have been using at 0.79mm (31 thou) since Septemebr 2010 until September 2011. I'll stick with my 0.74mm (29thou) as the engine is now superb!

ETA: (03Nov'11)
The revised NGK plug 03C 905 601A VW have introduced on the Scirocco 1.4TSi 160PS is NGK PZFR6R8EG. The "8" refers to the plug gap... 0.8mm. Link to description. As before, plug heat range is still "6". Mechanically they are the same plug. Link to description

The safe way of gapping these wire tip electrode plugs. Note the comment about breaking the tip if you are rough with them.

C.