Vauxhall has issued a strongly-worded statement insisting its cars do not have any emission test detection devices – despite the suggestion by BBC’s Panorama that they do.

Such ‘defeat device’ software as used by Volkswagen has been proven to detect test conditions and alter engine settings to produce fewer harmful NOx emissions than in real-world driving.

The Panorama test appeared to show a disparity between tailpipe emissions of a Vauxhall Zafira Tourer 1.6 diesel when strictly run under official test conditions and when a single parameter – the temperature of the engine – was changed.

The engine ‘outside’ test cycle conditions produced three times the amount of NOx as the test cycle-compliant engine. This could indicate the presence of software that detects a vehicle is undergoing an emissions test.

Not so, says Vauxhall. Its products “comply with all regulatory requirements, including the in-service emissions testing program, according to EU rules. These requirements are periodically audited by the approval authority.”

Vauxhall: Panorama used a poorly-performing car

So what caused the difference in emissions found by Panorama? Either a test that wasn’t correctly set up, insists Vauxhall, or a vehicle that was not performing correctly.

“Panorama has refused to share information on the technical accuracy of the test prior to the broadcast.”

This lack of information is why Vauxhall believes the car was not performing as it should: when Panorama conducted the emissions test strictly by the book, NOx emissions were still twice as high as legislation permits.

Panorama also ran the Zafira Tourer through a regular real-world procedure, and found that NOx emissions went “off the scale” of the testing equipment.

A test engineer at the Czech Republic lab used by Panorama said that although emissions will increase in real-world driving, it should be by ‘tens of percent’.

“There is no reason for the emissions to be three times, five times, ten times higher.” Vauxhall did not respond to this observation in its statement.

[ut_togglegroup] [ut_toggle title=”STATEMENT IN RESPONSE TO PANORAMA – BBC 1 20.30 HRS NOVEMBER 23RD NOV 2015″ state=”closed”]Vauxhall has clearly stated that its vehicles do not have any feature that detects that a vehicle is undergoing an emissions test, including any feature that would respond to wheels turning.

Vauxhall products comply with all regulatory requirements, including the in-service emissions testing program, according to EU rules. These requirements are periodically audited by the approval authority.

We suspect that the vehicle tested (Zafira 1.6 diesel) was not performing correctly and/or the test execution was not correctly set up. In order that Panorama did not potentially draw the wrong conclusions from their testing we requested full test reports and data from the testing including how the vehicle and test was set up, the technical state of the vehicle and details of the pre-conditioning of the vehicle which is necessary to achieve a stabilised condition for the test.

Panorama has refused to share information on the technical accuracy of the test prior to the broadcast.

When DUH tested the Zafira in Germany they were not willing to share their results before they went public. We subsequently concluded that the campaign contained misleading elements. In response to the incorrect accusations of DUH we ran a full series of tests. Those tests proved that the Zafira 1.6 meets all the legal emission limits both in 2WD and 4WD roller testing. Those 4WD tests were conducted under the supervision of the TUV agency and officially protocolled.[/ut_toggle] [/ut_togglegroup]