The Volkswagen diesel scandal has brought increased scrutiny on how new cars are tested for emissions and fuel economy.

VW's use of "defeat device" software to cheat on laboratory emissions tests could cause regulators to put greater emphasis on on-road emissions testing.

But, in Europe at least, there is some debate about which entity will conduct that testing.

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Last December, the European Union set up a Committee of Inquiry into Emission Measurements in the Automotive Sector to investigate compliance with emissions standards, noted Wards Auto.

The committee will release non-binding recommendations in February, including a proposal for the creation of a new agency that could take over responsibility for emissions testing covering all 28 EU nations.

This has led to some debate among EU lawmakers, with Dan Dalton—a member of the European Parliament—arguing that responsibility for emissions testing should remain with individual national governments.

2010 Volkswagen Golf TDI

2010 Volkswagen Golf TDI

Proponents of EU-wide emissions testing believe it would harmonize the myriad testing procedures used by individual countries, and make it harder for manufacturers to slip "defeat devices" past authorities.

German transport minister Alexander Dobrindt cited the case of a Fiat model tested by German authorities.

It was found that the Fiat switched off its emissions controls after 22 minutes—two minutes longer than the emissions-test cycle.

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German authorities argued that this constituted an illegal "defeat device," but Italian authorities disagreed, Dobrindt said.

Testifying before the emissions committee last month, Dobrindt called for the tightening of a 2007 clause that allows "defeat device"-type software in order to protect engines.

Kathleen van Brempt—the chair of the emissions committee—recently indicated support for some form of unified EU emissions-testing protocol.

2017 Fiat 500X

2017 Fiat 500X

In a recent letter, she cited an "evident lack of control" over emissions testing, and called for "systematic enforcement" of emissions standards.

That could include fines levied by the European Commission on cheaters, the letter noted.

MORE: Peugeot admits real-world gas mileage is far lower than ratings

Non-compliance with European emissions standards goes well beyond Volkswagen, recent studies and disclosures have indicated.

A recent study of 230 diesel-car models by advocacy group Transport & Environment (T&E) found that not one model met current Euro 6 emissions standards in real-world driving.

In July, PSA Peugeot Citroën admitted that the real-world fuel economy of most of its gasoline and diesel models was much lower than official ratings, a conclusion based on an internal audit.


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