I'm an affected owner with a 170 Yeti. I've received notice that the 'fix' is ready. As timing would have it my car is booked in for a service on Friday, therefore I've been doing a lot of research....

My conclusion is that I'm going to decline the fix for now.

There's a lot of information out there on the 'effects' of the fix, but very little info on what the 'fix' actually does other than obviously removing the defeat code. However, I came across this reported letter from Audi which I thought I'd share:-

5 December comment here:-

http://www.honestjohn.co.uk/news/volkswagen-emissions-scandal/8-reports-of-volkswagen-tiguans-losing-power-after-ea189-emissions-fix/

Extract:-

===================================================

"In response to your request for a more detailed explanation of the “advances in diesel combustion technology”, I can confirm that the update includes a revised fuel injection pattern, meaning that the number of injections, as well as the timing of those injections are changed. An additional fuel injection phase has been added but as it is formed from part of the fuel quantity of the main injection there is no negative effect on fuel consumption. Specifically, this additional fuel injection phase takes advantage of technology that was not available at the time the affected vehicles were manufactured.

In essence, the affected vehicle’s injection phase has been split from a single injection into multiple injections which results in an improved burning process in the engine. The software update also increases the affected vehicles’ Exhaust Gas Recirculation (EGR) rate, which results in lower nitrogen oxides (NOx) production. Improvements in the combustion process ensure that this increase in the EGR rate (which lowers NOx levels) does not have a detrimental impact on particulate levels.

I hope this information is sufficient for your concerns and offers you reassurance that the software update will not adversely impact your vehicle.

Kind regards

Executive Office

Audi UK "

=================================================

A 'stratified' charge is a, now common, technical advancement in DI engines both petrol and diesel.

Will VW produce the amended graphs to show the actual new outcome?.

Like SCR it might actually be a win for those with the old EGR tech..........?.

That looks like it has half a chance of actually being a true description of what has been done. I'd have to say I'm a little sceptical that they can up the EGR rates without any increase in particulates; but admitting that they've upped EGR rates is progress towards believability at least.

Thanks for posting, PaveyArk. :)

Edited 11 January, 20179 yr by Wino

I would hope that a stratified charge would significantly reduce particulate matter (extend DPF life) and better control combustion temperature peaks also meaning less need for the EGR to interfere and thus extend its life too.

Found this on PistonHeads:

 

https://onedrive.live.com/?authkey=%21AII8a0cFXX1v3Qs&cid=B6B727C7F19316F7&id=B6B727C7F19316F7%212722&parId=B6B727C7F19316F7%21104&o=OneUp

 

Not sure how the figures have been taken or even how to verify them. Interesting if true

I would hope that a stratified charge would significantly reduce particulate matter (extend DPF life) and better control combustion temperature peaks also meaning less need for the EGR to interfere and thus extend its life too.

Stratified charge is spark-ignition engine only, isn't it?

SCCI is stratified charge compression ignition is apparently the very latest , but I'd be surprised if it's that advanced as a fix

Stratified charge was introduced on DI petrol engines as a means of overcoming the usual issues associated with leaning out a petrol engine. No reason it couldn't be implemented on a diesel, though it'd be done during the expansion stroke rather than compression to feed in more fuel once the initial charge has lit up.

 

Last I checked, SCCI was still experimental. It's a nightmare to control accurately.

 

I was thinking about the whole NOx mitigation thing the other night, particularly in the context of cars not equipped with SCR. One of the ways in which NOx is dealt with is in passive regen of the DPF: is it possible they've gone for increasing particulate generation in the combustion cycle so that there's more particulate matter in the DPF, increasing the capacity to consume NOx in passive regen?

 

DPF life is primarily a function of oil ash loading which is independent of particulate loading. Unless the DPF is being consistently prevented from regenerating, increased particulate loading shouldn't have much of an impact on its working life.

Complete and utter MBF I think!

 

AIUI SCCI would require injectors capable of cycling twice (or more) during the latter part of the compression stroke and first part of the power stroke. "The fix" does not involce either new injectors or a new, faster ECU, so it can only be a software fix.

 

The question then becomes "if the desired/required fuel economy and emissions could be achieved by driving the current injectors differently, why was this not done in the first place?" again.

Complete and utter MBF I think!

 

AIUI SCCI would require injectors capable of cycling twice (or more) during the latter part of the compression stroke and first part of the power stroke. "The fix" does not involce either new injectors or a new, faster ECU, so it can only be a software fix.

 

The question then becomes "if the desired/required fuel economy and emissions could be achieved by driving the current injectors differently, why was this not done in the first place?" again.

No-one's saying it's SCCI - that's a different engine control technology entirely.

 

As for why didn't they do it day one? They had a solution that meant they didn't need to?

 

That aside, these engines started development about 10 years ago. Combustion research has moved on quite a bit in that time so it's very possible they've found better ways to control the injection and combustion process in order to improve engine function without needing new hardware.

 

From what one owner reported in another thread, the structure of the files/data on the ECU changed quite substantially after the update so it's more than just a simple remap. If they're able to change the control routines for the different components in the ECU, then they've got quite a lot of latitude to make improvements.

No-one's saying it's SCCI - that's a different engine control technology entirely.

 

As for why didn't they do it day one? They had a solution that meant they didn't need to?

 

That aside, these engines started development about 10 years ago. Combustion research has moved on quite a bit in that time so it's very possible they've found better ways to control the injection and combustion process in order to improve engine function without needing new hardware.

 

From what one owner reported in another thread, the structure of the files/data on the ECU changed quite substantially after the update so it's more than just a simple remap. If they're able to change the control routines for the different components in the ECU, then they've got quite a lot of latitude to make improvements.

Look, I am a software engineer; there is a difference between changing the organisation of the data space in an EEPROM and changing the data and/or the control code. Doing one of them does not imply, much less require, that you have done either of the other two.

WTF's MBF?

Look, I am a software engineer; there is a difference between changing the organisation of the data space in an EEPROM and changing the data and/or the control code. Doing one of them does not imply, much less require, that you have done either of the other two.

I'm not sure if you're familiar with how engine controllers are laid out, but typically the software routines and the map data are in separate blocks.

 

Remaps typically just involve changing the data maps to change fuelling, turbo boost control, etc. while leaving the control routines untouched. Addresses for specific parts of the map don't change and the control software sees no change in operation.

 

If VAG have gone to the trouble of reorganising the data structure on the ECU it points to them having made changes to the control software too: at the very least they'd have to change the data address for the control routines to point to. It's a lot more work and would be stupid from an engineering point of view if they were just changing the maps. Now it might be as simple as needing to increase the data space for some of the maps to allow more fine-grained control over a particular parameter. If the storage on the EEPROM is fixed then other maps would have to be shrunk to accommodate this. Or there's space available to just make it bigger, other stuff still has to be moved out of the way for it.

WTF's MBF?

WTF is WTF? ;)

 

Male Bovine Faeces.

I'm not sure if you're familiar with how engine controllers are laid out, but typically the software routines and the map data are in separate blocks.

 

Remaps typically just involve changing the data maps to change fuelling, turbo boost control, etc. while leaving the control routines untouched. Addresses for specific parts of the map don't change and the control software sees no change in operation.

 

If VAG have gone to the trouble of reorganising the data structure on the ECU it points to them having made changes to the control software too: at the very least they'd have to change the data address for the control routines to point to. It's a lot more work and would be stupid from an engineering point of view if they were just changing the maps. Now it might be as simple as needing to increase the data space for some of the maps to allow more fine-grained control over a particular parameter. If the storage on the EEPROM is fixed then other maps would have to be shrunk to accommodate this. Or there's space available to just make it bigger, other stuff still has to be moved out of the way for it.

I get all that, but we were originally told that they were "removing the defeat device". All that should require them to do is suspend or delete a condition with pseudocode like:-

 

Program EMS is

Declarations

BN_US_EMISSIONS_TEST_MODE : Boolean := False

AR_EMISSIONS_TEST_MAP : Array <> of natural := {values}

other declarations

 

Begin

Other code

 

If {however this is determined to be the case} then

    BN_US_EMISSIONS_TEST_MODE := TRUE

End if

 

Other code

 

If BN_US_EMISSIONS_TEST_MODE then

    Fetch AR_EMISSIONS_TEST_MAP

End if

 

Other code

 

End EMS ;

 

From that pseudo-code you delete the second conditional, and that's all you actually need to do.

You could maybe delete the data table that is no longer required too.

Edited 12 January, 20179 yr by KenONeill

This is a talk by two guys who did a lot of research into the technical and non-technical aspects of 'Dieselgate' (including a bunch of reverse engineering work on the ECU):

 

It's about an hour long but worth watching in its entirety for context on this issue.

 

The short version of what VAG did is that the ECU ran two maps: one for emissions compliance during test and the other for normal on-road operation. Neither are fully fit for purpose. The emissions compliant map has higher fuel consumption and lower performance than the as-sold vehicle specification. The on-road map is not EU5 emissions compliant.

 

So, simply deleting the defeat device code is not sufficient to solve the problem. The challenge VAG have faced is in satisfying both sets of criteria, which leads us back to the topic here which was a discussion of the ways in which this might be achieved.

So in the real world of 2017 in Europe the German Government Agency approved the VW 'Fixes' and time will tell the honesty of that happening.

The Defeat device is no longer present if vehicles are in for the Fix and nobody has to have the fix done because if Governments make it compulsory in Europe / EU 

then VW will have to pay out much more than are getting away with.

The EU will have to decide were Defeat Devices Illegal, the UK Transport Secretary in October 2015 said illegal since 1989 but then did nothing about very much.

New Transport Secretary now in the UK doing not very much it seems.

 

In the USA , VW & Bosch have plead guilty, employees have been charged, investigations continue, some Fixes are approved and fines are being paid.

I'm an affected owner with a 170 Yeti. I've received notice that the 'fix' is ready. As timing would have it my car is booked in for a service on Friday, therefore I've been doing a lot of research....

My conclusion is that I'm going to decline the fix for now.

There's a lot of information out there on the 'effects' of the fix, but very little info on what the 'fix' actually does other than obviously removing the defeat code. However, I came across this reported letter from Audi which I thought I'd share:-

5 December comment here:-

http://www.honestjohn.co.uk/news/volkswagen-emissions-scandal/8-reports-of-volkswagen-tiguans-losing-power-after-ea189-emissions-fix/

Extract:-

===================================================

"In response to your request for a more detailed explanation of the “advances in diesel combustion technology”, I can confirm that the update includes a revised fuel injection pattern, meaning that the number of injections, as well as the timing of those injections are changed. An additional fuel injection phase has been added but as it is formed from part of the fuel quantity of the main injection there is no negative effect on fuel consumption. Specifically, this additional fuel injection phase takes advantage of technology that was not available at the time the affected vehicles were manufactured.

In essence, the affected vehicle’s injection phase has been split from a single injection into multiple injections which results in an improved burning process in the engine. The software update also increases the affected vehicles’ Exhaust Gas Recirculation (EGR) rate, which results in lower nitrogen oxides (NOx) production. Improvements in the combustion process ensure that this increase in the EGR rate (which lowers NOx levels) does not have a detrimental impact on particulate levels.

I hope this information is sufficient for your concerns and offers you reassurance that the software update will not adversely impact your vehicle.

Kind regards

Executive Office

Audi UK "

=================================================

The extract clearly refers to "....meaning that the NUMBER OF INJECTIONS...." which I take to mean a stratified charge

But

Agree, hard to believe that they would consider retrofitting such tech on an 'old' engine.......it's the knowledge doubling every 12 months thing that make everything almost impossible to keep up with unless you're at the cutting edge in the business

I've posted this in the legal action thread, but I think it's relevant to this topic too (perhaps more so) so forgive me for cross-posting:

 

ADAC in Germany tested a Golf CR140 and conclude the update slightly improves power and torque: https://translate.googleusercontent.com/translate_c?depth=1&hl=en&ie=UTF8&prev=_t&rurl=translate.google.ie&sl=de&sp=nmt4&tl=en&u=https://www.adac.de/infotestrat/tests/eco-test/diesel_messung/default.aspx%3FComponentId%3D266205%26SourcePageId%3D31832&usg=ALkJrhiZX1XoW0GjR_WPKMqECOAr3iOpFw

 

(Original German article: https://www.adac.de/infotestrat/tests/eco-test/diesel_messung/default.aspx?ComponentId=266205&SourcePageId=31832)

 

They report a modest increase in CO2 emissions while also finding that real world CO2 emissions pre-update were higher than those recorded in type approval testing. In a similar vein, they found higher fuel consumption pre-update compared to the type approval, and higher post-update.

NOx emissions increased slightly on the NEDC after the update, but given that pre-update values were using cheat mode, this has to be seen as an improvement. Two other drive cycles considered more representative of real-world driving reported substantial improvements in NOx emissions. https://www.adac.de/_mmm/jpg/Diagramm_03_758x649_266238.jpg

 

CO2 emissions on all three drive cycles went up slightly (a few percent at most). ADAC comment that there's a variability of +/- 2 % in the data due to experimental uncertainty in any case and conclude the variation is almost inconsequential. https://www.adac.de/_mmm/jpg/Diagramm_04_719x697_266240.jpg

I unfortunately got the fix yesterday (in India).

My Yeti 4X4 2012 had a routine annual maintenance appointment, and after leaving the car, the service guy called to check if I wanted it. I asked what it does, and he replied "nothing in particular it's a routine upgrade". In the middle of work and meetings, in a hurry, I said yes.

 

When I went to pick the car I asked him what the upgrade does. He wasn't coherent. He did mention I wouldn't feel any difference in performance. That to me, is a polite way of saying the performance will reduce, but not by much.

 

Don't know if it's psychological, but I do feel the car doesn't pull as strongly as it used to from first gear the moment you start releasing the clutch (something that I really enjoyed). Meaning low rpm torque has reduced? I have sent an email to Skoda asking them for details of what they have done. Haven't heard from them yet.

 

Is there any way to undo this?