US economy tests to include 'driving cycles and conditions encountered in normal use', regulatory body warns
25 September 2015

Car manufacturers have been warned that their vehicles will undergo real-world tests for emissions in the United States, in the wake of the VWdefeat device’ scandal.

The United States Environmental Protection Agency, whose NOx emission test was bypassed by the software installed in VW’s EA189 engines, has sent an open letter to vehicle manufacturers today. In principle the purpose of the correspondence is to advise car makers that the vehicles they send in for testing are likely to be returned with higher mileages than normal - but the letter also sends the clear message that the EPA is now determined to make it more difficult for any maker to use software and different vehicle modes to pass the testing procedure.

The letter reads, “The EPA may test or require testing on any vehicle at a designed location, using driving cycles and conditions that may reasonably be expected to be encountered in normal operation and use, for the purposes of investigating a potential defeat device.”

It adds, “Such testing can be expected in addition to the standard emissions test cycles when Emissions Data Vehicles and Fuel Economy Date Vehicles are tested by EPA. Manufacturers should expect that this additional testing may add time to the confirmatory test process and that additional mileage may be accumulated on the EDVs and FEDVs.”

Manufacturers are unlikely to put up any resistance to the additional mileage - although there may be concerns about the extra time taken to approve vehicles’ fuel economy figures, and whether that could delay potential launches and model roll-outs, particularly as the EPA gets up to speed on the new real-world test elements.

Read more on the Volkswagen emissions scandal:

How the Volkswagen story unfolded

Reports suggest VW was warned of illegal software 'years ago'

How VW's 'defeat device' works

Top VW bosses to leave

Prosecutors to investigate Martin Winterkorn

PSA Peugeot Citroën leads calls for tougher emissions test procedures

Your key questions answered

BMW - why the X5 complied with independent US emissions test

Blog - it's time for firm action in the wake of the VW emissions scandal

Blog - what really happens in an official economy test

Blog - It's time VW started talking to its customers

Blog - thinking about buying a VW diesel? Carry on regardless

Blog - the VW Scandal and the growing dangers of its ripple effect

Blog - VW's scandal has put the entire motor industry under pressure

Blog - Winterkorn pays a high price

Blog - the emissions scandal could sink Volkswagen's US ambitions

Blog - are we about to see the death of diesel?

Blog - VW's US boss faces the music

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26 September 2015
Woah! That sounds almost like common sense. Unexpected from a regulatory body. Let's hope it's catching and we get that in Europe.
Then maybe have the quoted mpg as something that 80% of drivers should be able to achieve.

27 September 2015
I am sure most drivers said there Car returned nowhere near the quoted figures,but,why has it taken so long,and for a major global problem for something to done?,has the emissions set be to low for Car makers to attain?,once VW has been punished for doing this,a root and branch of the whole industry should be carried out?

Peter Cavellini.

27 September 2015
It was only ever a comparasion tool. These real world tests will still be in a Lab and BMW VW will still beat Renault,Ford GM etc.

typos1 - Just can’t respect opinion

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