VW in US about to be slapped with mammoth emissions fine

[kalniel]

If nobody else here has ever worked in automotive, that is sixty levels of bull****.

You don't have to have worked in automotive to see that

[PorcupineTime]

Yes VW, we totally believe that two rogue engineers forced you to cheat tests on eleven million cars.

[DR]

Four more carmakers join diesel emissions row

Mercedes-Benz, Honda, Mazda and Mitsubishi’s cars are shown to emit significantly more NOx pollution on the road than in regulatory tests

http://www.theguardian.com/environme...P=share_btn_tw

[kalniel]

Now that I don't mind in the slightest. We know that the tests are rubbish, so to say they emit more in the real world isn't any kind of scandal.

[DanceswithUnix]

Now that I don't mind in the slightest. We know that the tests are rubbish, so to say they emit more in the real world isn't any kind of scandal.

Yes, I think there is a big difference between cars that are engineered to do well in the testing to cars that cheat in the testing.

Given Euro 6 NOx level limits are about the same for petrol and diesel engines, I would love to see how good/bad petrol is these days in similar real world testing.

[badass]

Some Audi owners are probably in denial that they're driving golfs

They have the same chassis and engines but they feel very different to drive. I've got an 8P A3 and a MK5 Golf.

Feel very, very different. Amazing what a bit of sound deadening, suspension settings and power steering calibration can do to a cars character..........


And marketing.

[kalniel]

Yes, I think there is a big difference between cars that are engineered to do well in the testing to cars that cheat in the testing.

Given Euro 6 NOx level limits are about the same for petrol and diesel engines, I would love to see how good/bad petrol is these days in similar real world testing.

That petrol don't need urea traps suggests they're probably better in the real world, but as usual it'll depend on how they're set up - the most efficient could well be worse if they're especially lean burn.

One thing I noticed on the Audi site is the quoted CO2 emissions have gone up for most of the cars, and they now more accurately reflect changes based on trim/wheel size. My A3 got certified at something like 108g/Km CO2, but same car is now 114.

[Butcher]

The V5 certification for NOx on my petrol Audi is 0.01, which is 6 times lower than the limit. That suggests that either the petrols have the best defeat device going, or that they are a lot better on NOx.
Generally I wouldn't expect petrols to be anywhere near the levels the diesels are putting out, even under real world conditions. Petrol catalytic converters are very good at reducing NOx.

[directhex]

The V5 certification for NOx on my petrol Audi is 0.01, which is 6 times lower than the limit. That suggests that either the petrols have the best defeat device going, or that they are a lot better on NOx.
Generally I wouldn't expect petrols to be anywhere near the levels the diesels are putting out, even under real world conditions. Petrol catalytic converters are very good at reducing NOx.

Petrol engines are *much* better on NOx than diesel

Diesel is a bit better than petrol on CO2

The world (and car manufacturers) have been concentrating on talking about CO2, because "carbon" is the big phrase, but NOx is worse for short-term localised health effects (CO2 contributes to global warming, NOx contributes to asthma attacks & cancer)

[Zak33]

messy...isn't it?

[Zak33]

my largest worry is the "head in the sand" mentalility.. "I didn't know.. I was on my yacht and just saw the result on email via my sat broadband and thought, "get in there my son"..(that's my invention.. not reality)

“To my understanding this was not a corporate decision,” Horn said. “This was something individuals did.”

individuals.. yes.... who reported into other individuals..... etc

[DanceswithUnix]

individuals.. yes.... who reported into other individuals..... etc

I can see how some engineers can be bullied into doing things that aren't ethical. People have tried it with me, without success, but it makes for a fairly challenging conversation and not everyone will have the tenacity and confidence to handle it.

I would expect any large organisation to have an ethics reporting line though, and people should feel they can use it without reprisal. That is a job for the man at the top.

[abaxas]

A modern petrol car with diection injection are polution monsters. Current diesels (with exception of NOx) are much cleaner.

[kalniel]

A modern petrol car with diection injection are polution monsters. Current diesels (with exception of NOx) are much cleaner.

Petrols surely have lower soot particules and NOx, so what pollutants are they bad for?

[Zak33]

the easiest words to understand that I've found are thus from Click Green

Carbon monoxide or CO – Carbon monoxide, produced by petrol engines when a car is warming up, is lethal and there have been many accidents involving carbon monoxide poisoning

• Suspended particulate matter or SPM – this is what the tiny particles emitted from the exhaust of a diesel engine are called. Soot is a tell-tale sign of SPM. Modern diesel engines are usually fitted with filters to lessen the amount of SPM emitted, but the bigger problem lies with older diesel engines that do not have particulate filters

• Hydrocarbon or HC – Hydrocarbons contain harmful chemicals such as benzene, which causes cancer. Petrol engines emit higher levels of HC than diesel

• Nitrous oxide or NOx – Nitrous oxide combines with the lowest level of the ozone layer to form smog. New diesel engines produce a higher amount of NOx than new petrol engines, but petrol-powered cars produce more NOx as time goes by.

As we can see, when it comes to carbon monoxide, carbon dioxide, and hydrocarbons, it’s better to go with diesel engines. However when it comes to particulate matter, diesel engines lose to petrol. Both stand on equal ground when it comes to nitrous oxide.

in my opinion the quote about petrol cars getting worse with time reflects engine wear and potential oil burning

[Butcher]

That click green thing is a bit wrong though.

CO is a problem, but not really at current concentrations (catalytic converters are very good at CO removal), it certainly used to be a big problem with petrol cars. Likewise hydrocarbons.
Both are indeed less of a problem in diesels, due to the excess air which makes diesel catalysts very effective at removing CO and HC.

The NOx thing they have the wrong end of the stick though. There is no "lowest level of the ozone layer" involved (given the lowest layer of the ozone layer is actually many kilometres up). The issue is that NOx is broken down by sunlight and produces ozone. Ozone is really bad for humans, hence the problem. Nitrogen dioxide (part of NOx) is also really bad for humans and gives smog its characteristic brown colour.

Also diesels are significantly worse than petrols on NOx, due to petrol catalysts being very effective at reducing it (typically about 95%), while diesels have no NOx reduction, unless they have a urea (AKA adblue) system or a NOx trap. Both of those are more like 50-80% efficient, hence the much higher NOx levels from diesels. Even with Euro 6 diesel NOx regulations still allow more NOx than petrol; Euro 6 for diesels is the same as Euro 4 was for petrols on NOx.

Also some interesting stats here: https://www.london.gov.uk/sites/defa...20report_0.pdf
Check the second table on page 28. Real-world Euro 6 diesels are emitting around 6 times more NOx than petrols, and Euro 5 are more like 17 times!