GDI Engines and Coking Valves

Loadmaster748

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Aug 2, 2019
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I've read for some time about the potential issues with the GDI engine and coking valves after 30k plus miles.

If you have such an engine, what's your view on it and what are the costs and options for remedial action, should your engine be affected?

I've already been put off the 'kangarooing' 1.5 unit and now there's the issue with the GDI.
 

Steve Caney

Active Member
Dec 8, 2019
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I have just bought a 2.0 tsi 2019 model... the EA888 Gen 3 tsi engine also has port injection which tends to keep the valve stems clean.
So coking is no longer an issue and has been this way for quite a while.
 

black_sheep

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Mar 10, 2013
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I have just bought a 2.0 tsi 2019 model... the EA888 Gen 3 tsi engine also has port injection which tends to keep the valve stems clean.
So coking is no longer an issue and has been this way for quite a while.

I was under the impression that the multi-port injection was removed with the latest version of this engine fitted with the GPF (MY2019s tested under WLTP onwards), hence why the OP has probably asked the question.
 
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SRGTD

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May 26, 2014
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I have just bought a 2.0 tsi 2019 model... the EA888 Gen 3 tsi engine also has port injection.......

VAG’s EA888 Gen 3 2.0 litre TSI engine lost the port injection as part of WLTP changes - at least it did in the Golf R, Golf GTI and Audi S3 - not sure about Seat models with this engine, but if port injection was deleted for other VAG models, it seems logical it might also have been deleted for Seat models using this engine. Maybe worth doing a visual check under the engine cover in your car to see if the port injection components are there (port injector fuel rail, port injector loom connector and fuel pressure sensor).

The Gen 3b variant of the 2.0 litre EA888 engine in the Polo GTI did retain dual injection, post-WLTP; confirmed by GTI owners over on uk-polos.net forum who have WLTP complaint cars.
 

Loadmaster748

Roll on summer.....
Aug 2, 2019
304
126
Surrey, UK
I was under the impression that the multi-port injection was removed with the latest version of this engine fitted with the GPF (MY2019s tested under WLTP onwards), hence why the OP has probably asked the question.
Absolutely - Having looked at both the i30N Performance and Leon Cupra, my understanding is that both have GDI units and, therefore, will be prone to upper side valve coking issues and all that goes with it, post 30k miles.

This is a very real issue which is a by-product of the manufacturers needing to meet emissions requirements.
 

Steve Caney

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Dec 8, 2019
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@Loadmaster748 @r@d00 @SRGTD @black_sheep

Most of the WTLP regulation rumours refer to USA with different emission regulations.

I can confirm this as FACT because,as I said in post responding to the OP,I have the Port injection rail on my MY2019 2.0 tsi.

I do not think the OP was thinking of a Cupra as he was talking about the 1.5tsi.

I will post a link with pics in a while when I find it. be right back.

Edit... the 2.0 tsi does not have kangerooing problems either.
 
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Loadmaster748

Roll on summer.....
Aug 2, 2019
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Surrey, UK
@Loadmaster748 @r@d00 @SRGTD @black_sheep

Most of the WTLP regulation rumours refer to USA with different emission regulations.

I can confirm this as FACT because,as I said in post responding to the OP,I have the Port injection rail on my MY2019 2.0 tsi.

I do not think the OP was thinking of a Cupra as he was talking about the 1.5tsi.

I will post a link with pics in a while when I find it. be right back.

Edit... the 2.0 tsi does not have kangerooing problems either.
Yes, I'm referring to the current Cupra...
 

black_sheep

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Mar 10, 2013
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@Loadmaster748 @r@d00 @SRGTD @black_sheep

Most of the WTLP regulation rumours refer to USA with different emission regulations.

WLTP is a European regulation, despite the ‘w’ referring to ‘worldwide’.

I found the following documents that are a very useful comparison for UK/EU/US/RoW emissions during a recent study I completed at work:

https://d2ou7ivda5raf2.cloudfront.net/sites/default/files/2019-06/booklet emission PC19 low v2.pdf

I don’t know the exact reason for the multi-port injection removal; however, my engineering judgement would point towards the fact that if the emissions are achieved using GPF, then why add additional equipment (cost, time) during manufacture if not required.
 
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SRGTD

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May 26, 2014
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WLTP is a European regulation, despite the ‘w’ referring to ‘worldwide’.

I found the following documents that are a very useful comparison for UK/EU/US/RoW emissions during a recent study I completed at work:

https://d2ou7ivda5raf2.cloudfront.net/sites/default/files/2019-06/booklet emission PC19 low v2.pdf

I don’t know the exact reason for the multi-port injection removal; however, my engineering judgement would point towards the fact that if the emissions are achieved using GPF, then why add additional equipment (cost, time) during manufacture if not required.

I think there may also be some benefits to mpg and emissions with direct injection compared to multi-port / direct injection. So maybe VAG needed to go to direct injection for some (most?) of the performance cars in their model ranges In order to achieve acceptable figures for WLTP certification; a GPF in conjunction with a multi port / direct injection set up might not have been sufficient for WLTP certification.
 

SRGTD

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May 26, 2014
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My point is, what are owner's views of the fact that GDI engines will most likely be gunked up in 30k miles.
I’ve not seen much - if any - reported issues on forums, although that might be down to many forum members leasing or PCP’ing their cars these days, so they don’t ‘own’ them long enough to experience carbon build up issues.
 

black_sheep

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Mar 10, 2013
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I think there may also be some benefits to mpg and emissions with direct injection compared to multi-port / direct injection. So maybe VAG needed to go to direct injection for some (most?) of the performance cars in their model ranges In order to achieve acceptable figures for WLTP certification; a GPF in conjunction with a multi port / direct injection set up might not have been sufficient for WLTP certification.

It will be interesting to see what engine Cupra use in the Mk4. 250 ps with 48v hybrid or diesel like all of the new Audi ‘S’ cars? New emissions rules in 2021(but 95% compliance required in 2020), mean that manufacturers have to achieve average of 119 g/km across their range (not an exact figure defined yet as manufacturers of larger cars i.e. JLR will have a slightly higher average target).
 

SRGTD

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May 26, 2014
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It will be interesting to see what engine Cupra use in the Mk4. 250 ps with 48v hybrid or diesel like all of the new Audi ‘S’ cars? New emissions rules in 2021(but 95% compliance required in 2020), mean that manufacturers have to achieve average of 119 g/km across their range (not an exact figure defined yet as manufacturers of larger cars i.e. JLR will have a slightly higher average target).
Yes, it will be interesting. If it follows VW and the mk8 Golf, the forthcoming mk8 Golf GTI was originally going to have a petrol / electric hybrid power plant. However, it’s now going to be petrol only - an updated version of the EA888 engine, to be available in two power outputs 242 bhp and 287 bhp. No news yet on the mk8 Golf R power plant.
 

Steve Caney

Active Member
Dec 8, 2019
40
16
I think there may also be some benefits to mpg and emissions with direct injection compared to multi-port / direct injection. So maybe VAG needed to go to direct injection for some (most?) of the performance cars in their model ranges In order to achieve acceptable figures for WLTP certification; a GPF in conjunction with a multi port / direct injection set up might not have been sufficient for WLTP certification.

This may well be true, as the engine I have also has the Budack cycle implemented, which was probably sufficient to ensure WLTP certification in this guise, but unable to satisfy performance criteria at the top end of the market.
 

RUM4MO

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Jun 4, 2008
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Maybe it is just the similar but different higher output versions of the 2.0TSI engine found in the Cupra and above Leons that lost their port injection.
 

Loadmaster748

Roll on summer.....
Aug 2, 2019
304
126
Surrey, UK
I’ve not seen much - if any - reported issues on forums, although that might be down to many forum members leasing or PCP’ing their cars these days, so they don’t ‘own’ them long enough to experience carbon build up issues.
Yes, those leasing for a period of three or four years really won't find this concern at the top of their list.

For those who have bought, or are buying, with their own cash, I'm surprised that nobody's really saying much about it.
 
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