Hi Gents,

 

My eldest son bought a low mileage, 1.2 TSI Fabia from a big Skoda dealer two months ago. He is completely non- mechanically minded and called me the other day to say that the Check Engine light was on. He took it back to the dealer who checked it out and said it would take a few days because the problem involved an expensive repair and the warranty company would want to examine the car before authorising the work.

 

I had a garbled version of what went wrong from him, and finally emailed the company to get clarification, but the service manager  didn't give an exact enough description to satisfy my curiosity. This is what they say:

 

 

 

The vehicle had a missfire, after we carried out a compression test we found that cylinder 3 was low causing the missfire problem. We refered to a Skoda bulletin for this problem which stated that soot particles may be causing the valve not to seat correctly causing the missfire. The repair procedure is to order a new cylinder head kit that also comes with a new cat. this repair was carried out.

 

I'm uncertain whether they replaced the whole cylinder head or just the affected valve / valves, and am puzzled about how soot build up can cause a valve to burn /leak.  I'd have thought that in a low mileage engine (27000) the gas flow through the exhaust valve would have blasted away any soot. My best guess from the above report is that maybe the fuel injector (if the engine is direct injection) has got dirty and started to run the cylinder lean, eventually burning the valve to cause a leak.

 

The car being a four year old, low mileage one, might have led a very gentle life, possibly leading to an injector getting sooted up - but that is just a guess.

 

Can any of you much more clued up gents shed any light on this problem please?

 

Thanks for reading and for any light you can shed on this.

 

 

Tony

Edited 3 July, 201312 yr by EvilV

Sorry to hear about the problems you are having. 

 

We had a piston ring failure on our 1.2 tsi Yeti after 10000 miles. Skoda replaced the engine. The original engine used to drink oil for a past time. The replacement has used negligible oil in the last 10000 miles. 

 

Sounds like a similar issue. I think that if it has been run gently for four years that as you say the build up of soot could have caused this. Although i do think there are issues with some of the early examples of this engine. 

 

Would suggest that your son keeps a close eye on the oil level and runs the engine hard periodically after any running in suggested by the garage...

 

Hope this helps

As far as I know it is not a common problem. But like all modern petrol or diesel engines they do benefit from being blasted periodically and not being run too gently. The TSI is very torquey at low revs and it encourages drivers not to rev the engine which in turn, over time gums up the works. The other thing is to use a good quality fuel. Try to avoid cheap supermarket stuff with only second grade cleaners and detergents, and use some of the big brand stuff such as Shell which keeps the engine really clean. The supermarket stuff has improved lately but there bread and butter blends are still a bit behind with cleaners. You can also use a fuel injector cleaner from time to time which really works well.

Thanks for those thoughts. I thought that since Skoda have produced a bulletin about it, and a repair kit, there must be  quite a few episodes like this. I will tell him to make sure he gives it a bit of a blast now and then. Maybe a Skoda mechanic will spot the thread and chip in with their experience and some clue about whether it is likely to recur. If this car hadn't been under warranty, the bill might have been bloodcurdling.

It's a misconception that supermarket fuel radically differs from 'branded' fuel, the big names supply all of the supermarkets, the tankers have different livery but the fuel comes from the same refineries.......

Quite a number of components have been updated on this engine; the block and head part number changed in November 2011 and the pistons have had three changes, the last one in Nov 2012.

 

 

TP

It's a misconception that supermarket fuel radically differs from 'branded' fuel, the big names supply all of the supermarkets, the tankers have different livery but the fuel comes from the same refineries.......

 

Yes, that's true but different additive packs used in the fuel for different brands and it can make a difference even though, as I said in my earlier post, the supermarket brands have come on quite a bit these day and are not at all bad for the money. It was notice the supermarket stuff doesn't always give the same mpg in the tests carried out on the tv recently so are not always cheaper. It's down to the additives. The additives are electronically metered into the fuel at point of pickup for each brand and controlled by the fuel dispatcher and the drivers electronic ID/order card. Been there and seen it all happen, except when I went they still put the additive packs into the tankers by hand.

Shell was not so pleased when the Super Additive of one of their improved formulations was revealed to be Sodium Chloride. (basically common salt.)

 

Octane might & does matter with some engines but lets face it for petrol in this country we get stuff that meets the minimum standards in 95,

97, 98, 99 ron etc.

 

Millions of vehicles driving perfectly well on decent fuel and engine oils.

Bought at Sainsbury, Asda, Tesco, Morrisons etc

This is not a 3rd world country with Low Grade or contaminated fuel, and it is 2013, so little excuse for anything less than good fuels be it Supermarket or Branded/more expensive..

 

So basically the car manufacturers like VAG need to build and sell engines that will run on the worst fuels & oils, dusty conditions  around the world and last and do a few hundred thousand miles.

Yet they fail to build consistently ones that can get to 30,000 miles without problems in the very unchallenging UK.

 

I would worry less about petrol bought and used and think more that its just another poorly built engine or poorly Quality Controlled parts.

 

http://www.royaldutchshellplc.com/2013/04/24/will-shells-new-v-power-nitro-plus-fuel-ruin-car-engines

Shells Scientists & testers must just have been have a bad decade back in the 80's.

 

george

Yes I remember the 80's Shell debacle. It blew up my mates Rover engine and Shell admitted liability, paying for his repairs. If you remember, they were inundated with claims. I'm no eggspurt on fuel but last year when I was involved in some engine testing where we were determining what fuel grades worked best in actual practice, we found fuels with more of the second grade detergents really do burn the dirtiest. We were not even looking at brands, just the best ron rating to use but just couldn't help noticing how big the difference was. We knew on paper what should work best from the engineering point of view but in practice that isn't always the way it works out. Even when we ran standard 95ron from two different brands we got very different results. Turned out one of the fuels was from a leading supermarket. We suspected as much but had it confirmed later. It dirtied our engine in the bench tests. We found one of the most expensive brands not only cleaned out the engine but kept it clean and improved efficiency. Again that was no suprise but it's always nice to see it in the flesh so to speak. The average driver doesn't notice the difference in normal driving unless you look inside your engine.

Shell was not so pleased when the Super Additive of one of their improved formulations was revealed to be Sodium Chloride. (basically common salt.)

 

I think that the source of that revelation was a non-chemist who got hold of completely the wrong end of the stick.  Sodium chloride is not BASICALLY common salt - it IS common salt.  Whats more it is totally insoluble in organic solvents - including petrol or diesel.  My guess would be that the additive(s) contained organic molecule(s) containing sodium and chlorine atoms that when burnt left a deposit of sodium chloride as an ash.

The 1.2 Tsi  is a fine engine and a VERY popular choice throughout the Vag range. I researched it well before buying mine and in comparison to the vast number out there, the engine is sound and reliable. All engines have their "Friday models"

As for fuel, I would never use Supermarket fuel, I leave them to sell cabbages and onions and buy fuel from a garage forecourt :p I used to use the Supermarket stuff until they cocked up with their diesel additives locally and had to close their pumps down for a while until they sorted it, after having wrecked a few engines along the way. I have no proof that SM petrol is any different, I just don't go there.

Yes, that's true but different additive packs used in the fuel for different brands and it can make a difference even though, as I said in my earlier post, the supermarket brands have come on quite a bit these day and are not at all bad for the money. It was notice the supermarket stuff doesn't always give the same mpg in the tests carried out on the tv recently so are not always cheaper. It's down to the additives. The additives are electronically metered into the fuel at point of pickup for each brand and controlled by the fuel dispatcher and the drivers electronic ID/order card. Been there and seen it all happen, except when I went they still put the additive packs into the tankers by hand.

I record all my fuel usage and dispute totally that supermarket fuel gives lower mpg than "top" brand.

 

Data for my last 2 cars over 6 years (I can give more detailed data if anyone is interested):

 

2006 Octavia 1.9TDi - supermarket 7,200 miles at 50.9mpg, branded 18,400 miles at 50.9mpg, premium branded 11,300 miles at 51.3mpg

2010 Octavia 1.8TSi - supermarket 5,500 miles at 36.6mpg, premium supermarket 1,700 miles at 37.1mpg, branded 17,900 miles at 35.8mpg, premium branded 4,200 miles at 36.4 mpg

 

The "branded" data is predominantly Shell and BP, the supermarket data is all Sainsbury and Morrisons except for a single fill of Tesco diesel

 

As you can see these are figures over significant mileages not just a single fill to see what it will do.  I am a chemist not a statistician but to me (and remember that I can see the individual results inside those averages) THEY ARE ALL THE SAME!!

Your results are perfectly valid eccleshill for your situation. But that's not what the tv programs tell us when they did there clinical analysis, results posted on here somewhere if you search. From engine tests we did on the bench it doesn't always produce as much power either. But it will differ from engine type to engine type, that much is apparent from our testing. Supermarket fuel is fine in most engines but it does have this tendency to burn a bit dirtier from what we could see, and again, it will differ from engine type to engine type. That often means less power and less mpg in some engines. Of course, to some extent, this will apply to the big brands too, but with less of a swing to dirtiness. Sorry to Evil for deviating from his original main thrust of his post although fuel could be a related matter to his situation.

Edited 4 July, 201312 yr by Estate Man

You can go online and find all the Specifications and Formulations for ESSO, BP, Tesco Momentum 99, etc.

Anything you want to know about the product.

You can Ask the Supermarkets in writing about their fuel and they will tell you.

 

Royal Dutch Shell reveal very little, difficult if not impossible to find the Spec of fuels,

They give all Public stuff & company reports, but not which refineries or Depots or even countries the fuel is coming in from.

 

george

Your results are perfectly valid eccleshill for your situation. But that's not what the tv programs tell us when they did there clinical analysis, results posted on here somewhere if you search. From engine tests we did on the bench it doesn't always produce as much power either. But it will differ from engine type to engine type, that much is apparent from our testing. Supermarket fuel is fine in most engines but it does have this tendency to burn a bit dirtier from what we could see, and again, it will differ from engine type to engine type. That often means less power and less mpg in some engines. Of course, to some extent, this will apply to the big brands too, but with less of a swing to dirtiness. Sorry to Evil for deviating from his original main thrust of his post although fuel could be a related matter to his situation.

The day I believe any scientific analysis from a TV program is a LONG way off - never let the facts get in the way of a good story.  The journalists have a point to prove!  I find it especially amusing when the story involves chemicals - hence my deep skepticism of the sodium chloride in Shell fuel claim above.

 

I think the key is the cleanliness of burn.  My data is for a complete mix of fuels - 3 tanks of this, 2 tanks of that etc.  The reason I still use premium fuels despite no obvious improvement in mpg is because I hope(!!) that the improved cleaning agents keep the engine in good order to allow the "lower" grade fuels to give better mpg than they would if used exclusively.

There are only so many elements on earth and the world consists of Earth, Wind & Fire. (&H20)

 

Everything we have comes from the ground so even synthetic products must  actually be natural,

but just with some work done since they came out of the ground and some science produced something from them.

 

None of it is Rocket Science but then again its produced rocket science so that we can go get minerals from other planets.

 

its only internal combustion engines we are bothered about here,

surely after 100 plus years of building them Skoda/VW can get that sorted out properly.

 

george

I record all my fuel usage and dispute totally that supermarket fuel gives lower mpg than "top" brand.

 

Data for my last 2 cars over 6 years (I can give more detailed data if anyone is interested):

 

2006 Octavia 1.9TDi - supermarket 7,200 miles at 50.9mpg, branded 18,400 miles at 50.9mpg, premium branded 11,300 miles at 51.3mpg

2010 Octavia 1.8TSi - supermarket 5,500 miles at 36.6mpg, premium supermarket 1,700 miles at 37.1mpg, branded 17,900 miles at 35.8mpg, premium branded 4,200 miles at 36.4 mpg

 

The "branded" data is predominantly Shell and BP, the supermarket data is all Sainsbury and Morrisons except for a single fill of Tesco diesel

 

As you can see these are figures over significant mileages not just a single fill to see what it will do.  I am a chemist not a statistician but to me (and remember that I can see the individual results inside those averages) THEY ARE ALL THE SAME!!

 

*********

 

There are a lot of things that make evaluating fuel consumption in your own car very difficult. Engine mileage is one. new engines are tight for thousand sof miles and fuel consumption improves slowly as they bed in to say 20,000 miles. Also, time of year is a factor as winter diesel has more paraffins in it than the summer mix. The calorific value of the winter diesel is 10% lower than the summer sort, so you will see much worse fuel consumption in winter. This is exacerbated by increased use of lights, heater blowers and wipers. All that electrical activity means more load on the alternator and more fuel consumed.

 

In fact, it is impossible to make valid fuel consumption figures over a period of use in your own car because of these things. 

 

 

To Estate man

 

The tests I saw which showed fuel additives and power formulas had negative effects, were not carried out by journalists. They were carried out at the road transport research facility and involved an identical engine being tested in identical conditions on a dynomometer. They found that none of the additives had a beneficial effect and were an expensive waste of money. they actually reduced power output and fuel economy.I know you aren't commenting about over the counter additives Estateman, but that is what I saw. 

 

It is my understanding that all these fuels come from the same massive petrol refineries whether they are supermarket outlets or famous brands. the fuel industry and the aftermarket car products industry have been conning punters for more than sixty years.

Edited 4 July, 201312 yr by EvilV

The day I believe any scientific analysis from a TV program is a LONG way off - never let the facts get in the way of a good story.  The journalists have a point to prove!  I find it especially amusing when the story involves chemicals - hence my deep skepticism of the sodium chloride in Shell fuel claim above.

 

I think the key is the cleanliness of burn.  My data is for a complete mix of fuels - 3 tanks of this, 2 tanks of that etc.  The reason I still use premium fuels despite no obvious improvement in mpg is because I hope(!!) that the improved cleaning agents keep the engine in good order to allow the "lower" grade fuels to give better mpg than they would if used exclusively.

I think you just made the point very nicely. If you continually used the fuels with greater quantities of secondary grade cleaners in them, rather than the premium fuels with much more of the 1st grade cleaners, you would indeed notice a difference especially when going back to the higher grade fuel. Both Top Gear and Fifth Gear found the lower grade fuels to give less mpg, something tests by the AA and others found out long ago. Also the tv programs found lower power output from the lower grade fuels. Again something that is well know in motor engineering circles within which I mix. There are several reasons for that all to do with additives and the way the fuels burn, the way the ecu handles it, and cleanliness too come into it. All that is nothing new. But I guess you would have to see it for yourself like I have to be convinced.

Edited 4 July, 201312 yr by Estate Man

I do think the OP has been very unlucky. It would be most surprising if using one fuel or the other has caused the problem just so long as it was 95 or 98 ron.

 

I do hope you get the problem solved to your liking as soon as possible so that you can enjoy what IMO is a fantastic car.

I do think the OP has been very unlucky. It would be most surprising if using one fuel or the other has caused the problem just so long as it was 95 or 98 ron.

 

I do hope you get the problem solved to your liking as soon as possible so that you can enjoy what IMO is a fantastic car.

 

Thanks Horkin. I know he has the car back now, and he thinks all is well. They replaced parts of the engine (maybe even the whole head - you can see what the aftersales manager says in his quoted email up top) and they put on a new CAT. The lad thinks all is great, but he is not experienced enough to really evaluate whether the job is really sorted. All i know is the dealer says it was caused by soot leading to compression loss. Like I said above, I'm wondering if it ended up with a dirty injector and ran lean for too long, burning the valves on no 3 cylinder. I can't see soot physically obstructing the closure of a valve unless the engine was totally coked up. Even my 1960s old bangers (in the 70s) weren't that coked up and they had plenty of carbon in the heads and on the pistons.

Evil, if a cylinder is burning dirty for a prolonged period it will deposit soot on the exhaust valve and it's seat preventing proper closure, especially if the previous owner plonked it about at low revs. That sort of driving encourages the build up of soot and carbon, as you will know. Modern petrol engines produce a sticky brown soot/carbon due to various factors. It's not easy to remove once it gets a hold on a valve. This can lead to burning of the valve and seat over time and of course, the resultant compression loss. In addition, with these new direct injection petrol engines, the fuel is injected very precisely directly into the cylinder (of course) with virtually none of it going to waste in the cylinder scavenging process. Scavenging relying instead on pretty much just air from the fresh charge and in the case of this TSI engine this is best done using turbo pressure. Scavenging is an important part of exhaust valve cleaning.  And so in the TSI engines the exhaust valves and seats don't get cleaned in the same way as engines with indirect into the plenum chamber injection systems where some of the fuel charge with petrol in it cleans and cools the valve and seat. That doesn't matter as such, but does rely on drivers to give their TSI some beans now and again to keep the engine clean and the use of a good quality fuel is to my mind crucial in aiding that process.

 

Don't worry about the 1.2TSI, from all accounts they are very capable engines and completely bullet proof. The adjustments and updates carried out on the engine by VAG have mainly be precautionary to rectify the small number of engines that developed a problem or potentially could develop a problem. Your son has just been unlucky. Enjoy!

Edited 5 July, 201312 yr by Estate Man

Thanks for the info and explanation EstateMan. I will just relax and tell him to make sure he gives it the odd burst and not to slug it around at low revs all the time.

 

Reading your other comments about the 1.4tdi, which I have myself, I am going to change my driving style a bit. My natural tendency is to change up as soon as poss and I am often gear 5 by forty to forty five if the road is flat. the old 1.9 SDI used to thrive on that, but maybe not the 1.4TDI.

 

Cheers

Hi Evil, (nice name that!)

 

Yep, most of us find that on these 3 cylinder engines especially, they like the revs up a bit more than a four cylinder to avoid working too hard. It actually nearly always results in using less fuel. I obtained my best fuel economy by staying in fourth gear. Strange but true. I only ever used 5th once over 55 mph and it was actaully even better at 60mph and turning much more easily. I dynoed mine and could see where she was running best at it seemed to be at 60mph in 5th gear or above. Below that the emmissions went up and of course that meant she was using more fuel to pull 5th. Very similar story on the 1.6cr too. They don't give their best until around 60mph in 5th. Under that they tend to use a bit more fuel if 5th is engaged.

 

Anyhoo...have fun experimenting. Good luck.

Right!  I now know exactly what went wrong with the engine and what's been done. At least, I know as much as the  main dealers tech dept know. I just spotted an old pal of mine who was the workshop manager at the same dealership until about a year ago. I explained the ragged story as I knew it, and about half way through it he started nodding. 'It's a well known issue,' he said. 'We did quite a few of them.'

 

The issue is that on the 1.2TSI, on some cars, for no particular reason, the exhaust valves can get just a tiny bit sticky n the valve guide. When I asked him why, he said, it's a side effect of the drive to lower emissions and make cars greener - no lead to provide last ditch lubrication in that hell hole of an exhaust port. Think about it - no part of an engine ha such a horrible life as an exhaust valve. Searing hot and little or no lubrication and you're still expected to jump up and down fifty times a second on full beans, while basking in an 800 degree blast. 

 

He said that the kit is a complete new head, part of the exhaust and the cat and that it costs a small fortune. The good news (apart from the fact that we didn't have to pay) is that the new head has some modified parts, so it shouldn't happen again.

 

 

Glad we dealt with a reputable dealer. Any premium we paid on buying it has been well made up by the after sales service.

Edited 5 July, 201312 yr by EvilV

Cheers Tony, glad you are sorted. These things can take some sorting out. Sounds feasible as your mate explained it.

 

While your mate says its a well known issue I can't say I've heard of it and certainly we haven't had a string of similar problems on here, so lets hope that while it's 'well known' its' isolated cases.

One thing that is becoming more and more obvious is that all these climatic measures being included in engine design, do seem to be having an effect on reliability and it appears no manufacturers are without their problems.