Carmakers manipulate emissions tests

@MARK

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BBC News - 'Carmakers manipulate emissions tests'

Didn't we already know this?

The book of tricks available to carmakers during the tests includes techniques such as:

> disconnecting the alternator, thus no energy is used to recharge the battery during the test

> the use of special lubricants that are not used in production cars, in order to reduce friction

> turning off all electrical gadgets such as the air-conditioning or the radio

> Slick tyres are pumped hard to reduce rolling resistance.

> Brakes are adjusted, or at times even disconnected, to reduce friction.

> Cracks between body panels and windows are taped up to reduce air resistance.

> Sometimes they even remove the wing mirrors.
 

Mr E

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Its a game played by both sides - some fairly arbitrary tax banding around emissions, plus penalties for not achieving average CO2 levels across volume sales, coupled with a very loose testing regime.

It's always gone on in one form or another, whether it be the "special" spec of the press fleet, tweaked engines for performance tests, etc. It's become more of a game as governments have turned to use the results of such tests as a stick. The OEMs play the game, testing to the exact rules, in order to ensure compliance.

Although the tests probably don't tell you want you can achieve in real life (although I've never been far off) they do help with comparisons as you'll find most manufctureres follow the same regime.
 

st4

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As the tests are standardised and consistent they can still be used to benchmark models. A 320d iirc does better than a C220 so in real life it will to
 

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If they can get away with all the blatant cheats listed, I imagine they could also easily use special temporary ECU mappings to get drastically better results.
 

Spinal

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In other news, dihydrogen monoxide (which is used in the manufacture of at least 99% of mercs) can be lethal when inhaled. In it's solid form it can also cause loss of limbs after prolonged exposure and in its gasseous form it can cause severe burns.


Point it - it's all down to presentation... it's all "true" for the given conditions...

M.
 

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Not a surprise they're inaccurate though I am surprised by how far manufacturers can bend the rules.

As the tests are standardised and consistent they can still be used to benchmark models. A 320d iirc does better than a C220 so in real life it will to
True when comparing 2 cars the same age. But if you are want to know if a new car you are buying will be more efficient than your current, old car, you can't compare as the gap between real and stated emissions/MPG is getting wider over the years.

But you're right, if you take the figures with a pinch of salt, use them to compare cars of the same age and don't expect to achieve the stated results, then they are useful. It doesn't bother me that much but it would be better if they were vaguely realistic.
 

Igurisu

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OK, so they manipulate the emissions test to get lower readings. This then translates through to reduced road tax and lower taxes paybale for those driving company cars.

Maybe its just me, looks like they are doing the general motoring public a favour.

Of course some people are concerned about CO2 emissions, but you will still get a comparison of where a car ranks amongst its peers.
 

st4

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JimboDS said:
Not a surprise they're inaccurate though I am surprised by how far manufacturers can bend the rules.

True when comparing 2 cars the same age. But if you are want to know if a new car you are buying will be more efficient than your current, old car, you can't compare as the gap between real and stated emissions/MPG is getting wider over the years.

But you're right, if you take the figures with a pinch of salt, use them to compare cars of the same age and don't expect to achieve the stated results, then they are useful. It doesn't bother me that much but it would be better if they were vaguely realistic.
It's the same test and its clear from posts on forums that certain models are more efficient than older ones. There's BE c classss doing way better than mine
 

joecash

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any form "self" such as self testing, self regulation, self investigation will always be abused eventually. What is happening in case's such as that described here is not even the tip of the "self" iceberg.

its just another dose of horsemeat
 
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Cars are driven through the test by computer, whereas they were once driven by people. This way they can get the exact smoothness, RPM, sweet-spot, limited braking, etc.

Worst offenders are Hybrids, that start with an 'artificially' charged battery, and end the test empty. Not real world by a long margin.

Having said all that, OEM's do need to be able to replicate the test if asked. Some brands duped the US test and are having to pay every owner compensation for NOT hitting the claimed MPG figures. Expensive business if they take liberties.
 
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st13phil

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I imagine they could also easily use special temporary ECU mappings to get drastically better results.
A former industry insider who I trust told me a few years ago that "a certain German manufacturer, not of the car you drive, has code in their ECU that recognises the EC Emissions Test Cycle and automatically selects a different map".
 

Dieselman

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The book of tricks available to carmakers during the tests includes techniques such as:

> disconnecting the alternator, thus no energy is used to recharge the battery during the test

> the use of special lubricants that are not used in production cars, in order to reduce friction

> turning off all electrical gadgets such as the air-conditioning or the radio

> Slick tyres are pumped hard to reduce rolling resistance.

> Brakes are adjusted, or at times even disconnected, to reduce friction.

> Cracks between body panels and windows are taped up to reduce air resistance.

> Sometimes they even remove the wing mirrors.
Typical media twaddle.

Some of those are very valid, such as turning off consumers, but others are ludicrous suggestions given that the tests are carried out on static rolling roads, so there is no wind resistance to accommodate as that loading is added to the roller resistance.
 

NISFAN

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Typical media twaddle.

Some of those are very valid, such as turning off consumers, but others are ludicrous suggestions given that the tests are carried out on static rolling roads, so there is no wind resistance to accommodate as that loading is added to the roller resistance.
Correct :thumb:

...and turning off electrical loads like the radio and aircon, is hardly 'cheating', they obviously want a best case scenario. Only fair in my book.
 

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