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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

#81

Post by Bud »

mattlutze wrote: post #58
Bud wrote: post #29

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...

The source of the data is actually www.spritmonitor.de, which is a self-reporting mileage tracking site (like www.fuelly.com). With ~501k vehicles tracked and 8.885B kilometers tracked, the site represents ~17k kilometers per car of user-reported mileage information. Is this the best, or a reliable source, of information to start the reckoning/witch hunt to come? I'm not sure.

Probably not sufficient for legal action, since as you noted, the data is user-reported. Probably sufficient to provoke more rigorous testing, though.

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

#82

Post by Bud »

cLeEOGPw wrote: post #65
axx wrote: post #14

I think we all should agree that this is the same for every car manufacturer (except electric). Sure, european manufacturers are the target now, but i expect same results from all other manufacturers (including asian and american). Lab results never represent real street results. How could they? People drive differently and the outcome is based on many aspects that you can't reproduce in lab conditions.

> except electric Why? You have just been shown corporate cheat on tests. Why you would ever assume this has something to do with fuel type? I expect Tesla cheat as much as MB or BMW in their "range" test. And if you believe otherwise you are just someone who doesn't learn from his experience.

You "expect"?

Could you perhaps cite any data, any at all? It's not like we don't have a LOT of Tesla owners out there who are obsessively testing this, every day. Do you think they're just all part of the conspiracy?

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

#83

Post by happyscrappy »

Bud wrote: post #76
happyscrappy wrote: post #67

Earlier quoted context omitted.

GM claimed less improvement(aka cheated less), so your comment is wrong. Edit: Apparently I am wrong.

It's not my comment. It's data presented in the report. My comment is taken directly from the chart I cited. So if you want to quarrel with it, you need to quarrel with those who compiled the data, I suppose. You first misread my comment, and now you're misreading the chart, apparently, so let me explain: the chart I cited shows the percentage of claimed improvement in fuel economy which was actually delivered in rea…

Hmm. I think you are right, the caption and graphic conflict a bit.

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

#84

Post by Narretz »

dingdingdang wrote: post #79
ifcologne wrote: post #52

More fuel consumption, more CO2. Clear. But it's not the cheating story of VW, continued - that was about nitrogen oxide pollutants which was up to 40 times above what is allowed in the US. From the report: > All carmakers have been exploiting ever more flexibilities in the current official tests during 2013 and 2014, but detailed results from Spritmonitor in Germany (Figure 4) show that cars produced by Daimler, PSA…

"But for sure, I'll never reach the official 5.7 l/km with my car ..." --> are you driving a Russian tank? I drive a 10 year old not particularly efficient Vauxhall (UK) and it is doing ~17 km/l!

It's not very difficult to assume he means 5.7l / 100km

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

#85

Post by happyscrappy »

maxerickson wrote: post #78
jameshart wrote: post #45

Earlier quoted context omitted.

That goes against my subjective experience. The contribution of buses and trucks in US cities is also significant, and my sense is that EU regs on those vehicles are more stringent than US. I particularly tend to notice how much -noisier- large US vehicles are than European equivalents in a city traffic environment, which tends to correlate with lower efficiency.

Europe generally has more stringent regulation and worse pollution than the US. It's many more people in a smaller space. Noise isn't a good predictor though, a muffler is a drain on efficiency.

Actually the VWs that were emitting 40x pollution in the US were only 10x of the Euro regs.

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

#86

Post by vkjv »

mattlutze wrote: post #58
Bud wrote: post #29

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...

The source of the data is actually www.spritmonitor.de, which is a self-reporting mileage tracking site (like www.fuelly.com). With ~501k vehicles tracked and 8.885B kilometers tracked, the site represents ~17k kilometers per car of user-reported mileage information. Is this the best, or a reliable source, of information to start the reckoning/witch hunt to come? I'm not sure.

I thought the same. In my anecdotal experience, drivers tend to get much lower than the manufacturer mileage because they optimize for things other than fuel economy (e.g., speed).

My dad taught me lots of tips on conserving fuel and thankfully I've exceeded the sticker numbers on every car I've owned.

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

#88

Post by equa »

This is not good, but it is much different from the NOx cheat because consumers can easily measure MPG themselves, and do. For that matter it's commonly noted in car magazines that U.S. EPA MPG ratings are lower the E.U. ratings for the same car & drivetrain; I'm not sure the 50% number in the OP would be so high relative to U.S. tests.

It also speaks to the responsibility of the auto press for the NOx issue. They routinely report real-world MPG ratings for cars ("in our driving, we got __ MPG"), but haven't bothered to test real-world emissions despite all the other expensive gear they use to test car performance. Manufacturers and governments should be accurate and honest, but it's also the press that should be routinely verifying their accuracy.

Example of skepticism at the "extremely optimistic European cycle":

http://www.caranddriver.com/reviews/2017-audi-a4-prototype-d...

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

#90

Post by equa »

This is not good, but it is much different from the NOx cheat because consumers can easily measure MPG themselves, and do. For that matter it's commonly noted in car magazines that U.S. EPA MPG ratings are lower the E.U. ratings for the same car & drivetrain; I'm not sure the 50% number in the OP would be so high relative to U.S. tests.

It also speaks to the responsibility of the auto press for the NOx issue. They routinely report real-world MPG ratings for cars ("in our driving, we got __ MPG"), but haven't bothered to test real-world emissions despite all the other expensive gear they use to test car performance. Manufacturers and governments should be accurate and honest, but it's also the press that should be routinely verifying their accuracy.

Example of skepticism at the "extremely optimistic European cycle":

http://www.caranddriver.com/reviews/2017-audi-a4-prototype-d...

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