Emissions Scandal Expands: Mercedes-Benz, Honda, Mazda, and Mitsubishi (theguardian.com)

An anonymous reader writes: Volkswagen has taken some serious heat for deliberately circumventing emissions tests with "defeat devices" in some of their vehicles. While no other cars have been found to use specific devices to fool tests in the same way, we're now learning that many manufacturers still mysteriously perform worse in the real world. Last week, the Guardian revealed that diesel cars from Nissan, Hyundai, Citroen, Fiat, Volvo, and Renault emitted significantly more pollution in realistic driving conditions than the tests supposedly allow. Now, we learn that vehicles from Mercedes-Benz, Honda, Mazda, and Mitsubishi emit substantially more than they should as well. For example: "Mercedes-Benz's diesel cars produced an average of 0.406g/km of NOx on the road, at least 2.2 times more than the official Euro 5 level and five times higher than the Euro 6 level. Honda's diesel cars emitted 0.484g/km of NOx on average, between 2.6 and six times the official levels." This provides clear evidence that the automotive industry is designing its cars to follow the letter of the law (passing tests), but not the spirit (actually reducing pollution).

Comments

Maybe

[Anonymous Coward]

Or it reveals that the testing mechanism was always wrong. It's a leap to say that differences between the tests and "real driving" represent fraud, until it's proven that the cheating mechanism is actually there (as it is in VW).

Re:Maybe

[MatthiasF]

Wish I had mod points, but I agree with this sentiment. Tests present a statistical average but real-world terrain and human driving is all but average.

Re:Maybe

[tripleevenfall]

Obviously, it's important for a test to always be uniform. If you tried to test cars under "realistic" driving conditions the tests would all be different.

Realistic driving conditions are variations in temperature, terrain, traffic flow, etc.

Realistic driving conditions vary based on the habits of the driver.

Realistic driving conditions vary based on the condition of the car over time.

Maybe instead of ballyhooing these tests, we should apply common sense to them. Maybe we should see them as a group of data points and not a limits, guarantees, or absolutes?

Re:Maybe

[Rei]

Indeed. VW did very egregious cheating, deliberately detecting tests and then optimizing for them. It sounds like these others are not engaging a "test mode"; but have optimized themselves for conditions that are tested for (at the expense of power and fuel efficiency) while optimized themselves for power and fuel efficiency in conditions that aren't tested for. Not as egregious, but still clearly problematic. There's clearly gaping holes in the system.

It also puts to lie this massive increase in diesel cleanliness over the years. It's improved, no question, but not nearly as much as has been marketed, particularly in smaller, cheaper vehicles. The same old choice remains: you can get a ~15% increase in fuel efficiency by mass (~30% by volume), and thus ~15% reduction in CO2 emissions, by going with a diesel, but it'll come at the cost of a more expensive engine (has to be built stronger to handle the higher compression, all issues of additional pollution control systems aside) and will kick out more health-impacting pollutants. And it just comes down to chemistry: if you burn fuel in air at hotter temperatures and/or higher pressures, you favor the production of chemicals like NOx - high temperatures and pressures make nitrogen more reactive. And you're going to kick out more PM for similar reasons. The higher temperatures and pressures help with CO and unburned hydrocarbons (they favor more complete combustion), but the scale of the added NOx and PM problems are much greater.

Contrary to what they've been pretending, a major way that car manufacturers appear to have been reducing NOx emissions in diesels is simply by burning their fuel cooler / less efficiently in conditions that are being tested for, and hotter the rest of the time to keep their performance and efficiency numbers up.

Re:Maybe

[Anonymous Coward]

That makes zero sense. What you're suggesting is that we let automakers continue to destroy our environment, just so they can make profits, like they have some sort of god-given right to make a profit. It's this kind of whoring that has put the planet in the state it's in now. All automakers should be moving to 100% electric at this point anyway. Lowering the bar for emissions would be a step backwards.

Well, goodbye passenger car diesel!

[RoTNCoRE]

I don't think diesel passenger cars will be a thing much longer in North America after this. And time to change the tests to measure results in real world usage conditions.

Not surprising and can you blame them?

[flappinbooger]

The law says "pass this test" so they pass the test.

How is this different than standardized testing in schools? The state says "pass this test" so the teachers train the kids to pass the test.

Do they actually LEARN anything useful for the real world?

Do these cars actually have low emissions when driven in the real world??

You be the judge.

Re:Honda Diesel?

[beelsebob]

Why? It's not like Slashdot is a US centric web page... Why does it have to make special mention of the status in the US?

Re:Honda Diesel?

[halivar]

Why? It's not like Slashdot is a US centric web page...

In all actuality, it really is. Slashdot covers US politics to an extent that it covers no other country (or even perhaps all of them combined). And it's not "politics in America affects everyone", either: I can't for the life of me figure out why, say, a Scandi cares about H1B tech hires in California.