The Volkswagen diesel scandal has placed greater scrutiny on laboratory emissions testing of new cars pretty much around the world.
Over the year since the news of VW's use of illegal "defeat device" software first broke, other carmakers have come forward to confess errors or outright cheating in their own emission and fuel-economy tests.
Now the Australian Automobile Association (AAA) is taking matters into its own hands.
DON'T MISS: CA regulator to start testing VW TDI diesel modifications for all versions
The group is spending A$500,000 ($457,955) to conduct its own on-road emissions tests of 30 models, reports WardsAuto.
Australia's AAA hopes to see how the real-world results stack up to the official ratings—and it claims to be taking this action because the government won't.
The government does none of its own testing to ensure carmakers comply with regulations, AAA CEO Michael Bradley told Wards.
2016 Toyota Land Cruiser (Australian spec)
Most regulatory bodies—including the U.S. Environmental Protection Agency—conduct relatively few tests of their own, because of the high costs involved.
Carmakers typically test all their new vehicles, according to specific rules laid out by regulators, or contract with third parties to do so, and then submit the results to government agencies.
The AAA's tests of the first 10 vehicles is expected to end this month, with results available later this year.
UPDATE: Separately, a battle between the Australian club and Volkswagen Australia has escalated.
ALSO SEE: Emission, fuel-economy test issues spread: Mitsubishi, Daimler, others being investigated
It started with the AAA's demand that VW explain why it said Australia's VW buyers deserved no compensation for diesel models VW has admitted contain "defeat device" software used to cheat on U.S. emission tests.
VW Australia has now retaliated by withdrawing its cars from the AAA's annual "best cars" competition, with a local VW executive saying the club's public statements "inspire little confidence in its grasp of fundamental issues,” and accusing the club of being "hostile" to the company's cars.
The AAA re-ran last year's "best cars" contest with VW, Audi, and Skoda vehicles removed, despite VW's contention that none of the vehicles submitted were affected by the global diesel recall of 11 million vehicles.
The association hired Melbourne-based consulting firm ABMARC to analyze the data from the on-road tests and compare it to the official figures produced using laboratory tests.
Portable Emissions Measurement Systems (PEMS) on a Peugeot 308
The on-road tests utilize Australia's only Portable Emissions Measurement System (PEMS).
This is the same type of equipment used for on-road emissions testing in the U.S. and Europe—including the tests that uncovered Volkswagen's "defeat device" software.
The Australian tests will focus on popular models sold in that country, but AAA also plans to test VW TDI diesel models both before and after they are modified to come into compliance with emissions rules.
MORE: Peugeot admits real-world gas mileage is far lower than ratings
Such modifications have yet to be approved by regulators for VW and Audi models sold in the U.S.
The Australian testing program comes amid growing global skepticism over the efficacy and accuracy of laboratory emissions and fuel-economy testing.
Last month, PSA Peugeot Citroën admitted that real-world tests of 44 of its models revealed much lower fuel efficiency than had the official laboratory tests submitted for certification.