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Study: Some car models consuming around 50% more fuel than official results

transportenvironment.org

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Re: Study: Some car models consuming around 50% more fuel than official results

#21

Post by will_critchlow »

yc1010 wrote: post #2

"On average, two-thirds of the claimed gains in CO2 emissions and fuel consumption since 2008 have been delivered through manipulating tests" How deep does this rabbit hole go :( Here in Ireland the motortax for cars newer than 2008 is based on CO2 emissions, if motorists find their tax rising due to cheating by car manufacturers thats an unexpected and direct cost to their wallets.

"if motorists find their tax rising due to cheating by car manufacturers"

This doesn't require new enforcement or new taxes - a large part of the purchase price of petrol is tax.

Re: Study: Some car models consuming around 50% more fuel than official results

#22

Post by mpweiher »

emp_zealoth wrote: post #8
yc1010 wrote: post #2

"On average, two-thirds of the claimed gains in CO2 emissions and fuel consumption since 2008 have been delivered through manipulating tests" How deep does this rabbit hole go :( Here in Ireland the motortax for cars newer than 2008 is based on CO2 emissions, if motorists find their tax rising due to cheating by car manufacturers thats an unexpected and direct cost to their wallets.

Or maybe we abolish nonsensical, contrary requirements? Whoever actaully believed the fuel consumption figures is a fool. You cant have a 1,5t of a car and expect it to use only 5l/100km. That's a good rate for a goddamn motorbike (450ccm,one piston, dont exceed 90 km/h and you might reach 4,5l/100km) Its one fifth of the mass...

I actually drove my Golf TDI at around the level of 5l/100km in Berlin for many years. Carefully. My girlfriend's Polo is significantly below that. Of course, these cars aren't ton and a half, but more around a ton.

Re: Study: Some car models consuming around 50% more fuel than official results

#23

Post by rplst8 »

etimberg wrote: post #5

I went through to the actual report ( http://www.transportenvironment.org/sites/te/files/publicati... ) and found an infographic (figure 8) that shows some of the methods manufacturers can use to defeat tests. "Pushing the brake pads fully into the callipers reduces rolling resistance" is apparently one way. That makes me ask the question, why don't we do this already? If it reduces rolling resistance it probably als…

The primary reason is that keeping the pads just in contact with the rotor prevents water from collecting on the rotor surface. Wet rotors can affect braking performance and safety.

Re: Study: Some car models consuming around 50% more fuel than official results

#24

Post by _ambigu0us_ »

etimberg wrote: post #5

I went through to the actual report ( http://www.transportenvironment.org/sites/te/files/publicati... ) and found an infographic (figure 8) that shows some of the methods manufacturers can use to defeat tests. "Pushing the brake pads fully into the callipers reduces rolling resistance" is apparently one way. That makes me ask the question, why don't we do this already? If it reduces rolling resistance it probably als…

In car braking systems the pedal movement from depressed to pressed corresponds to a very small (With the brake cylinder fully compressed (as they did for the test), it requires several full pumps of the pedal to bring the pad into contact with the disk. This increases braking distance, which is generally considered a bad thing.

Re: Study: Some car models consuming around 50% more fuel than official results

#25

Post by Zigurd »

solaris999 wrote: post #7

This is the big next step that a lot of people were expecting - where in-depth studies into all of the competitors occurs and it's gradually revealed that this defeat device game has been played by almost everyone in the industry. It'll be interesting to see the repercussions for the automakers, but inevitably this'll end with sweeping legislation changes and reform of the testing protocol and standards.

This is a very good bet. The "defeat device" turns out to be using a feature of the ECU platform provided by the ECU supplier. It would be surprising to find that VW was the only maker to cheat, when the cheating mechanism was available to everyone.

There are some markets, like voting machines, where requiring open, buildable, verifiable code is good practice. Cars might be another.

Re: Study: Some car models consuming around 50% more fuel than official results

#26

Post by silon7 »

emp_zealoth wrote: post #8
yc1010 wrote: post #2

"On average, two-thirds of the claimed gains in CO2 emissions and fuel consumption since 2008 have been delivered through manipulating tests" How deep does this rabbit hole go :( Here in Ireland the motortax for cars newer than 2008 is based on CO2 emissions, if motorists find their tax rising due to cheating by car manufacturers thats an unexpected and direct cost to their wallets.

Or maybe we abolish nonsensical, contrary requirements? Whoever actaully believed the fuel consumption figures is a fool. You cant have a 1,5t of a car and expect it to use only 5l/100km. That's a good rate for a goddamn motorbike (450ccm,one piston, dont exceed 90 km/h and you might reach 4,5l/100km) Its one fifth of the mass...

It's achievable with a diesel and not too-heavy foot easily (possibly with some extra NOx ;-)

Re: Study: Some car models consuming around 50% more fuel than official results

#27

Post by Zigurd »

wil421 wrote: post #18
mgiannopoulos wrote: post #4

So, any Japanese or American companies doing this as well? Who's next?

For now the answer is inconclusive, but let's wait and see what tricks the gasoline models are playing. The Chevy Cruze Diesel was as clean as promised in the US version but the European version may not be as clean[1]. http://www.thetruthaboutcars.com/2015/09/tech-dive-chevy-cru...

The US Cruze diesel uses urea injection. That works. The cheats seems to be trying to do without that.

Re: Study: Some car models consuming around 50% more fuel than official results

#29

Post by Bud »

If you read the full report, the automaker with by far the largest gap between its claimed improvements in fuel economy and its actual on-the-road performance is General Motors. Much worse than VW and Mercedes (who also did very poorly), by this measure.

A reckoning is coming.

source: see page 13, here

http://www.transportenvironment.org/sites/te/files/publicati...

Re: Study: Some car models consuming around 50% more fuel than official results

#30

Post by verinus »

fithisux wrote: post #17
yc1010 wrote: post #2

"On average, two-thirds of the claimed gains in CO2 emissions and fuel consumption since 2008 have been delivered through manipulating tests" How deep does this rabbit hole go :( Here in Ireland the motortax for cars newer than 2008 is based on CO2 emissions, if motorists find their tax rising due to cheating by car manufacturers thats an unexpected and direct cost to their wallets.

Not their wallets. why should they pay for the fraud of corporates? Let the corporates replace cars .

Perhaps this is a kind of occasion where people know that things are too good to be true but want them believe them to be...

edit: typo

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