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Nearly all new diesel cars exceed official pollution limits

theguardian.com

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Re: Nearly all new diesel cars exceed official pollution limits

#41

Post by teh_klev »

kuschku wrote: post #35
teh_klev wrote: post #30

Earlier quoted context omitted.

> in particular insisting that they couldn't require the diesel exhaust fluid tank to be topped up by the end user Not being rude, but I'm having trouble parsing that part of your comment. Do you mean that the US authorities won't let diesel car owners re-fill the diesel exhaust fluid tank by themselves, i.e. the re-fill must be performed by a dealer? Also is the DEF tank just a US thing? I'd never heard it before (U…

The DEF tank is a global thing – ever heard of AdBlue etc? But yes, the issue is that the US requires dealers to refill them. And also sets a limit for how often refill cycles may happen. And the weight of the tank sets a limit on how large it may be. The result is simple: Small Diesel cars can’t exist legally in the US.

This is all completely new to me (and probably most folks unless they're running around in brand new diesel vehicles). The last diesel car I owned was a 1998 (Euro-2 standard when NOx emissions were more relaxed - so no DEF required [0]) Ford Mondeo which I disposed of in 2006 when the timing belt snapped ruining the engine. Since then I've owned older petrol engined high mileage "bangers" so I would never have encountered DEF unless I won the lottery and fancied a new Landrover :)

[0]: https://en.wikipedia.org/wiki/European_emission_standards#Em...

Re: Nearly all new diesel cars exceed official pollution limits

#42

Post by pbhjpbhj »

mhw wrote: post #23

While it makes good headlines, I think most of this could be summed up as "vehicle emissions are more complex than the simple model you might expect". Go and read the Wikipedia page on the New European Driving Cycle - https://en.wikipedia.org/wiki/New_European_Driving_Cycle . Notice that in the test procedure every instance of acceleration is described as "the car slowly accelerates". Now think about the range of dri…

>I think there's an awful lot of "floor the accelerator to get back up to the speed limit" as well //

When I took my UK driving test (quite a few years ago) my instructor informed me that I needed to accelerate hard on a [uphill] dual carriageway section in order to not be perceived as "failing to make progress" (ie. keeping up with traffic). I wonder if modern tests take account of safer aspects of fuel economy, such as slower acceleration, or if it's still penalised?

Re: Nearly all new diesel cars exceed official pollution limits

#43

Post by ptaipale »

kuschku wrote: post #35
teh_klev wrote: post #30

Earlier quoted context omitted.

> in particular insisting that they couldn't require the diesel exhaust fluid tank to be topped up by the end user Not being rude, but I'm having trouble parsing that part of your comment. Do you mean that the US authorities won't let diesel car owners re-fill the diesel exhaust fluid tank by themselves, i.e. the re-fill must be performed by a dealer? Also is the DEF tank just a US thing? I'd never heard it before (U…

The DEF tank is a global thing – ever heard of AdBlue etc? But yes, the issue is that the US requires dealers to refill them. And also sets a limit for how often refill cycles may happen. And the weight of the tank sets a limit on how large it may be. The result is simple: Small Diesel cars can’t exist legally in the US.

>The result is simple: Small Diesel cars can’t exist legally in the US.

And that is, of course, intentional. To keep some of the foreign competition away.

Re: Nearly all new diesel cars exceed official pollution limits

#44

Post by teh_klev »

lucaspiller wrote: post #36
teh_klev wrote: post #30

Earlier quoted context omitted.

> in particular insisting that they couldn't require the diesel exhaust fluid tank to be topped up by the end user Not being rude, but I'm having trouble parsing that part of your comment. Do you mean that the US authorities won't let diesel car owners re-fill the diesel exhaust fluid tank by themselves, i.e. the re-fill must be performed by a dealer? Also is the DEF tank just a US thing? I'd never heard it before (U…

This page from Land Rover has a good overview, apparently it's a new requirement in Europe (I've also never heard of it before): http://www.landrover.co.uk/ownership/euro-6-emissions-standa...

"A third warning indicates when 515 miles are left and also warns that the DEF tank needs re-filling or the vehicle will not be able re-start when the distance countdown reaches 0."

Wow.

"The engine will only start again when the DEF tank is re-filled."

And thus the the "faulty DEF sensor" malfunction is introduced into our car fault lexicon.

Re: Nearly all new diesel cars exceed official pollution limits

#45

Post by codecamper »

My feeling is that catalytic converters go the wrong way.

The biggest problem today is global warming. We want to stop burning diesel. By hiding the NOx, there is less of a problem with burning diesel so we burn more. That's sort of a hard ass approach, but.

Also using a catalytic converter also saps some energy and so requires more diesel to be burned and so more CO2 released.

Re: Nearly all new diesel cars exceed official pollution limits

#46

Post by lb1lf »

f_allwein wrote: post #6
stinos wrote: post #3

Earlier quoted context omitted.

I thought it was common knowledge the lab tests are a joke? Has been posted on HN as well IIRC.

I thought it was more a case of "some car manufacturers cheated" and not "almost all diesel cars emit several times more than they should". How is this possible?

Also, the number of car manufacturers outnumber the number of car engine manufacturers - so if one company which actually makes engines (cough) optimizes their engines for testing, several car manufacturers may be caught with their trousers down. (Which, I am sure, will lead to all sorts of interesting lawsuits.)

For instance, the engine in cars as different as the Land Rover Defender (sadly, no longer among us) and the Volvo, say, S80 is basically the same Ford-engineered unit.

Re: Nearly all new diesel cars exceed official pollution limits

#47

Post by selimthegrim »

teh_klev wrote: post #44
lucaspiller wrote: post #36

Earlier quoted context omitted.

This page from Land Rover has a good overview, apparently it's a new requirement in Europe (I've also never heard of it before): http://www.landrover.co.uk/ownership/euro-6-emissions-standa...

"A third warning indicates when 515 miles are left and also warns that the DEF tank needs re-filling or the vehicle will not be able re-start when the distance countdown reaches 0 ." Wow. "The engine will only start again when the DEF tank is re-filled." And thus the the "faulty DEF sensor" malfunction is introduced into our car fault lexicon.

There's no limp mode?

Re: Nearly all new diesel cars exceed official pollution limits

#48

Post by SideburnsOfDoom »

stinos wrote: post #3
f_allwein wrote: post #2

> There is no suggestion that any of the cars tested broke the law on emissions limits or used any cheat devices. Since all these cars passed the laboratory test, that means there must be something very wrong with the test and the way the standards are enforced. Or all car makers do cheat.

I thought it was common knowledge the lab tests are a joke? Has been posted on HN as well IIRC.

> I thought it was common knowledge the lab tests are a joke

it was common knowledge for a long time that the lab tests were not the same as real world driving. But we thought that, even though the lab tests were better, there was some meaningful relationship.

As it turns out, they are wildly divergent in a lot of cases. And the repercussions are ongoing. Long-term, this might turn out to a turning point in the history of internal-combustion engines.

Re: Nearly all new diesel cars exceed official pollution limits

#49

Post by Symbiote »

kuschku wrote: post #40
MagnumOpus wrote: post #22

Earlier quoted context omitted.

> The simple fact is that based on the tests and the impact of NOx on population health, the sale of diesel cars should be stopped immediately Extremely disingenous. You know what happens when the sale of diesel cars/taxis/buses stops? The old ones get driven longer. You know what vehicles create the lion's share in NOx emissions? The ones built and sold before 2000 when Euro3 emission standards started limiting NOx…

> (This is probably similar to much of the rest of Europe) In Germany, we actually limited almost all cities to cars passing Euro 4, and many even to cars passing Euro 6. Cars get a sticker with a color based on which standard they pass, and the zones are limited to cars with a sticker of the proper color. So most busses in Germany are Euro VI now.

London's bus fleet is also pretty new. All meet Euro 4, and over 20% at least Euro 5. [1]

The taxis are the problem -- London's low emission zone (similar to those in Germany) only applies to large vehicles, taxis are not included. There are thousands of taxis over 10 years old still running in London [2].

> So most buses in Germany are Euro VI now.

Really? That would mean most buses in Germany are less than 3 years old, which seems unlikely.

[1] https://tfl.gov.uk/info-for/media/press-releases/2014/july/w...

[2] https://www.whatdotheyknow.com/request/spread_of_ages_of_lon...

Re: Nearly all new diesel cars exceed official pollution limits

#50

Post by Symbiote »

pbhjpbhj wrote: post #42
mhw wrote: post #23

While it makes good headlines, I think most of this could be summed up as "vehicle emissions are more complex than the simple model you might expect". Go and read the Wikipedia page on the New European Driving Cycle - https://en.wikipedia.org/wiki/New_European_Driving_Cycle . Notice that in the test procedure every instance of acceleration is described as "the car slowly accelerates". Now think about the range of dri…

>I think there's an awful lot of "floor the accelerator to get back up to the speed limit" as well // When I took my UK driving test (quite a few years ago) my instructor informed me that I needed to accelerate hard on a [uphill] dual carriageway section in order to not be perceived as "failing to make progress" (ie. keeping up with traffic). I wonder if modern tests take account of safer aspects of fuel economy, suc…

I took the test last summer.

Accelerating hard isn't a cause for failing, but after the test the examiner gives advice on driving style, particularly around "eco-friendly driving". (I was told I was too slow moving to higher gears.)

Example: https://www.learnerdriving.com/ld-system/driving-lessons/pro...

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