I've got a rather odd issue with my vrs at the moment. After driving it for 30 mins or so I occasionally get a flashing engine warning light and a bit of a misfire. It usually happens around 1800 rpm or on lift off from motorway speeds. As soon as I get back on the throttle the light stops flashing and it runs as it should.

I bought the car in May from the local Skoda main dealer and I took it back to them to have it looked at. It wasn't showing any error codes but it did have a lot of misfires registered. They performed some update that needed doing and sent me on my way. Needless to say it happened again just a few days later so it's going to have to go back to them.

It's a 2013 estate with the CTHE engine, full dealer history and 46k miles. Does anyone else have any experience of this problem? I've looked and looked but can't find anything similar on the web.

Did they just clear the fault codes showing misfires without removing all 4 spark plugs and since out fitting new ones?

 

What does the Full Dealer History show as far as when the Spark Plugs were last replaced.

Some say they last 40,000 miles, Main Dealers might, but i would expect it would by now have its 2nd replacement set in.

 

I would want to know what update was carried out, was it an Engine Managemen one, or a DSG or something else.

Full Main Dealer Service Histories should be showing this, otherwise not a full history.

 

Strange you can not find anything similar on the web.

There is a pinned thread at the top of the page and dozens of siimilar threads in this serction.

Edited 20 September, 20196 yr by Roottootemoot

Thanks for the reply.

I can find plenty of other posts about misfires etc but not with the same set of conditions as they are happening with mine. I had a good search on this site before creating this post.

Ithink it was an ecu update they did but I can't be 100% sure. The plugs were changed with the service it got before I picked it up and have done less than 2000 miles.

Is there an invoice for that service with the part number.

Since there are logged misfires enough are happening in a cycle but then the car is not going into limp mode.

The plugs need to come out including the more awkward one, they need inspected and the gap checked, 

and maybe the Dealership tech will need to consider the TPI and check the timing chain since it is a CTHE.

 

PS

? 

Are you running it on Super Unleaded 97 or 99 ron and not just 95 ron Unleaded?

Edited 20 September, 20196 yr by Roottootemoot

I'll have to have a look in the folder to see if I've got an invoice for the service. After reading up on misfire issues the plugs were my first thought, especially with it not showing any error codes. The service center looked on the system and told me they were all replaced at the last service. I suppose it is possible that they are not gapped correctly or one of them was dodgy.

Please excuse my ignorance but what is the TPI? Also, I didn't realise there was an issue with the timing chain, I'll look into that.

'Technical Product Information'  and there is one covering CTHE Timing Chains.

 

http://briskoda.net/forums/topic/438447-2012-2014-cthe-mk2-fabia--vrs-timing-chain-issues

http://briskoda.net/forums/topic/424866-vrs-timing-chain

There are other threads, but just dont let a Tech or Service Desk staff say not relevant.

 

Software Update.

http://briskoda.net/forums/topic/434190-cthe-new-software-for-misfires

?

What petrol are you using?

 

Edited 20 September, 20196 yr by Roottootemoot

I'm using super unleaded, usually the Tesco momentum or, occasionally, the BP stuff from the station near work. I'll have a read up that link you posted to familiarise myself with the issues 👍 

It just seems like an odd set of circumstances that cause the issue to me.

I forgot to mention that the first time it did it I was driving up a gentle hill and it seemed to hold on to 2nd like it was in sport mode, then the light flashed a couple of times, shifted up and stopped flashing. After that it behaved normally until about 30 mins into the drive home.

That is when you are on Supercharger and Turbo and the engine underload & that is commonly when there will be a misfire with a failing plug.

If i am roadtesting a car to see how it is i might well be in 4th or 5th and kickdown to get it down a couple of gears and if there is going to be misfires that is when they will be.

Almost always Engine Light is on Supercharger or Super & Turbo and it can also be the EPC or Both.

The other time is on Turbo above 3,500 rpm and then needing some throttle and the Supercharger is on demand below 3,500 RPM.

 

Driving on CC canhave that happen, the car is trucking along fine maybe at 70 mph and 2,400 rpm maybe and Cruise gives it a bit more and there is a misfire or 3.

That's interesting. So is your gut feeling that it could be something as simple as a dodgy plug? I possibly should have mentioned that I don't have cruise in mine but I wish I did as I find the speed seems to build steadily until my 70 becomes more like 85/90.

I might pull the plugs out in the morning and have a look at them or even just replace them and see if that cures it.

@Smogzilla

Do you have an Ignition Coil puller, or do you know how to do it wothout, or how to make a DIY?

Take care of the pipes as you move them and then replace. 

 

There is a guide by @UrbanPanzeron how to change the plugs in the 'Guide' section.

 

 

Edited 20 September, 20196 yr by Roottootemoot

I've got a puller so I should be alright. Doesn't look that bad a job to access the fiddly one, couple of vacuum hoses,oil pipe and the air duct. I'll pull them out and take a photo and put it up on here.

The plugs are a tad on the pricey side by the look of things 😬

About £10 each.

 

Be carefull with the 'O' rings of the Turbo Pipe.

 

Not a bad job, but then why do so many Factory Trained Techs or Full Time not so trained fitters **** it up, 

even the odd 'special technician; that trains others can co-ck it up.

Edited 20 September, 20196 yr by Roottootemoot

I'm not sure my local motor factors will have the recommended Denso plugs in but I can get Bosch ones from eurocarparts for £12 each or NGK for £20 each. The last time I bought a set of plugs I could have got all 4 for that 😆

I've got a box of o rings in the garage so I'll replace them if I've got the right size.

Swerve the NGK as that is the OEM plugs and the problem. 2009-2019 problem, they are stubborn, Audi techs knew to go DENSO.

Crazy price that.

 

Next issue Europarts.  Be careful it is the correct Bosch as they can get that well wrong.

An other menber seemingly had the wrong Bosch plugs fitted at a dealership recently, thread last week.

Odd one that, but dealerships never surprise me.

 

Just take care with the big O rings and seal everything or you will get the Engine light, and that is where we came in.

 

http://briskoda.net/forums/topic/471398-misfire-all-cylinders

 

Edited 20 September, 20196 yr by Roottootemoot

The part code for the Bosch plugs at eurocarparts is 408994660 if that means anything to you. So I'm expected to pull a set of NGK plugs out as that's what Skoda fit as standard?  I'll see what the local motor factors have in stock and hopefully get a set of Denso or Bosch and see if that cures it.

I dont do BOSCH but i can find the right plugs if you need.

That looks like the number for the ones for a 1.2 TSI.  Maybe what went wrong with the other members car and the RAX approved garage.

Why i said watch Europarts or supply the wrong parts.  STWP

 

 

Edited 20 September, 20196 yr by Roottootemoot

I'll just pull the current ones out and have a look at them then book the car back in for them to "fix" 

I'll post a shot or 2 of them when I have them out.

So I should find either Bosch or NGK plugs in there? I've been away from the vag scene since I got rid of my A3 1.8t about 10 years ago and it seems nothing has changed when it comes to them telling you what you should be using. That thing had the check engine light on that often that the dash looked odd without it. It was never off for more than a few weeks anyway.

So I pulled the plugs and 3 of them were like the first picture and one had slightly different deposits as seen in the 2nd picture.

They are NGK sizfr6b8eg and were gapped at 0.7-0.8mm. 

To be honest, I was hoping to see at least one of them in a state. They do look like they are only a couple of 1000 miles old.

 

 

Edited 21 September, 20196 yr by Smogzilla
Double picture

I would still put in new plugs, and the DENSO.   First clean those and have them at 0.7mm

If issues are continuing and it is misfires then best have the timing chain measured.

Assuming that the Ignition Coils are OK, the Intake and sealing is ok, no punctured breather from the last plug change.

 

Last OEM Plugs i removed from a CTHE were.

NGK PZFR6B8FG & 0.7mm gap.   (NGK 96498)

 

So you have SIZFR6B8EG  (NGK 96209)

Edited 21 September, 20196 yr by Roottootemoot

I've just booked it back in with the Skoda garage I bought it from to have it looked at again. While it's in there I'll order a set of the Denso plugs you posted earlier and fit them when I eventually get it back. Armed with the information you have given me I can at least sound like I know what I'm talking about when I deal with them.

Thanks for your help and I'll keep this thread updated until the problem is resolved.

Yes, the plugs that are in it now are NGK SIZFR6B8EG. Looks like I can get a set of Denso plugs for around £40 online. The local motor factors only have the same NGK plugs that are currently in it.

The Distributors usually have the choice of 3 or 4 plugs that come up on the Motor Factors screen and have them at the Factors in a day or 2.

Which is why i use my Local Motor Factor.

I would never buy spark plugs online unless a trusted seller, Livingston Autoparts etc.  Too many fakes out there.

or 

http://opieoils.co.uk

 

Hmm, most of the Denso plugs I'm seeing are on eBay or Amazon. I'll be wary of where I get them from. I might spend an hour phoning around locally to see if anyone can get me a set of the Denso ones then.

@Smogzilla - This may be your photography, but those plugs all look sooty to me.