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Volkswagen - Potential $18 Billion Fine


FROSTYBALLS
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Diesels are already on a down, with NOx being targeted.

I have one question. Will certain driving conditions cause the ECU to switch to clean mode?

The motoring journalists always liked German diesels over any other country's, and petrol versions. So for VAG diesel cars to drive well, the ECU has to be in "dirty" mode. Toyota diesels have been criticised by the journalists, for not matching VAG diesels cars performance.

Toyota's hybrid route looks the way to go.

Regarding motor journalists harping on about exciting driving, it does not matter in the current climate of clean, reliable, safe cars and road manners.

I can see more stunted performance and reliability issues with VAG diesels. The emission systems are having a hard time already.

VAG are in serious trouble!

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I watched BBC Newsnight last night and their lead story was about VW. They showed a clip from December 2014 where the Newsnight Technologies editor showed how car compaies in general enhance their test results. They are made so that the car senses when it is in test mode and goes into a standard test cycle for ultimate efficiency. Evan Davies asked the question as to why it has taken so long for the authorities to take action since they exposed it last December.

So they're all at it and let him without sin cast the first stone.

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I wonder if they can leverage this tech, maybe link it to a GPS, so cars go into a Low Emissions mode so they can go into places like London without getting shafted and into towns and villages and stuff, but then go back into 'normal' mode when on the motorway or country roads etc.

It would be quite a neat idea if it hadn't been used for deceptive purposes first!

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Downside with the idea of switching on the fly, is that M-ways and trunk roads also contain people, who are (not maybe!) affected by Nox. A lot is from HGV's but diesel and petrol cars contribute. Petrol more so as they age: fresh from the line they are lower in Nox but compression ratio increases with carbon deposits:) No free lunches…...

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I don't know so much about this compression ratio increasing because of carbon build up. As the carbon builds up on the piston crown and the valve heads etc surely it reduces the cylinder capacity? If you don't have the same volumetric capacity then surely this will cancel out any meaningful increase in compression ratio.

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I wonder if they can leverage this tech, maybe link it to a GPS, so cars go into a Low Emissions mode so they can go into places like London without getting shafted and into towns and villages and stuff, but then go back into 'normal' mode when on the motorway or country roads etc.

It would be quite a neat idea if it hadn't been used for deceptive purposes first!

I think that's a brilliant idea (apart from the concerns raised by cobh18) and I don't have any doubts that it could be done. I met a guy from New Zealand a couple of years ago and he was telling me that the milk tankers over there are constantly linked by Satnav to a government web site and when they come off the paved highway onto farm roads they automatically stop paying road tax until they come back on.

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Well, reasoning for having dynamic emissions control is because, atm, NOx concentrations in cities are high as there is so much concentrated slow moving traffic.

On the motorway and fast roads, you want to maximize your mpg, and NOx is less of a problem because it isn't concentrated and also there is space for it to be dispersed, so it's worth saving fuel and reducing CO2 emissions.

Anything with an EGR will already do this to a degree - Under light loads they are feeding exhaust gasses into the engine which lowers NOx production by suffocating the oxygen, but also increases fuel consumption, CO, CO2, particulates etc.

On the motorway/under load, the EGR will close which improves MPG and reduces CO, CO2 and particulate production at the expense of increased NOx.

Petrols produced very low NOx because they combust at fairly cold temperatures, and only suck in the exact amount of oxygen needed to burn whatever amount of petrol is sucked in, so all the oxygen is used up by combusting the petrol and there's none left to combine with the nitrogen. OTOH diesels run very very lean on average, so there's lots of free oxygen that, combined with the higher temperature combustion of diesel, makes them very prone to NOx formation.

Ironically, the 'eco' lean-burning petrols also tend to produce much higher NOx than normal petrols because of this; VW discovered this when they first came out with the FSI engines - In the 'stratified charge' mode they were producing much more NOx compared to 'homogeneous charge' mode and they had to add extra stages and catalysts to the exhaust to try and control it!

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  • 1 year later...

I was reading Honest John's Ask HJ page and followed subjects relating to diesel issues and finally got to this page -    

http://hanlonblog.dailymail.co.uk/2012/07/the-great-diesel-con-exposed/comments/page/2/#comments 

Then I looked at the comments to this blog and one from Ian Dee stood out. 

Quote

On the subject of excessive exhaust emissions there is a simple explanation. Diesel engines have a management system that allows them to conform to EU emission levels. The program reads the input from the vehicle as it is driven along the road, but it has two over-rides at least. One is that when it detects that the vehicle is being subjected to an emission test or a fuel consumption test it goes into a program that gives the best result, even though it would be very difficult to drive the car in that mode. The other mode is triggered when the driver decides to accelerate and pushes the throttle to the floor. This triggers a new mode, called open loop, that ignores, briefly, all the smart systems that will reduce pollution, and it pours excessive amounts of fuel into the engine to provide the maximum power irrespective of emissions. That produces the blast of black smoke from the exhaust so often seen as diesel cars and vans accelerate. Diesel is a con that should be exposed, but petrol is only part of the solution. Slightly more Co2 from petrol might be a lot better than poison and disease from uncontrolled diesel exhausts, and a lot more rain.

Posted by: Ian Dee | 25 July 2012 at 08:49 PM

Look at the date. 4 years ago, before it became big news. And it was in the Daily Mail of all papers!

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It's always a bad end to the week when the Daily Fail actually report something worth while :(

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10 hours ago, Konrad C said:

I was reading Honest John's Ask HJ page and followed subjects relating to diesel issues and finally got to this page -    

http://hanlonblog.dailymail.co.uk/2012/07/the-great-diesel-con-exposed/comments/page/2/#comments 

Then I looked at the comments to this blog and one from Ian Dee stood out. 

Quote

On the subject of excessive exhaust emissions there is a simple explanation. Diesel engines have a management system that allows them to conform to EU emission levels. The program reads the input from the vehicle as it is driven along the road, but it has two over-rides at least. One is that when it detects that the vehicle is being subjected to an emission test or a fuel consumption test it goes into a program that gives the best result, even though it would be very difficult to drive the car in that mode. The other mode is triggered when the driver decides to accelerate and pushes the throttle to the floor. This triggers a new mode, called open loop, that ignores, briefly, all the smart systems that will reduce pollution, and it pours excessive amounts of fuel into the engine to provide the maximum power irrespective of emissions. That produces the blast of black smoke from the exhaust so often seen as diesel cars and vans accelerate. Diesel is a con that should be exposed, but petrol is only part of the solution. Slightly more Co2 from petrol might be a lot better than poison and disease from uncontrolled diesel exhausts, and a lot more rain.

Posted by: Ian Dee | 25 July 2012 at 08:49 PM

Look at the date. 4 years ago, before it became big news. And it was in the Daily Mail of all papers!

I wonder what he drives?

Maybe its a blue police box :wink:

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