The Association says independent testing from the likes of Choice in Australia and Which in the UK found some models were unlikely to ever match the claims of their manufacturers.
The consumer groups claim some cars were out by more than 30 percent, and one model in the UK exceeded its official fuel figure by 133 percent.
Choice’s Matt Levey said current fuel consumption ratings were untrustworthy, adding that the events of dieselgate proved carmakers should not be involved in testing of their own products.
“We need fuel efficiency claims that Australians can trust, backed by genuinely independent testing and world’s best standards to help save on household fuel costs,” Mr Levey said.
Which in the UK found the Jeep Grand Cherokee 4WD used 11.6 l/100km on average, verses its official figure of 7.5 l/100km, while the BMW X4 needed 8.0 l/100km - 1.9 litres more its official rating of 6.1 l/100km.
Mitsubishi’s Outlander PHEV was also singled out, as its official fuel figure is rated at just 1.9 l/100km in Australia. This figure is reliant on a full battery charge, however, and Which found the figure rises to 4.8 l/100km consistently once that initial charge is exhausted.
Choice found similar results in Australia, saying people movers and SUV were the worst offenders.
The consumer group called for a three-point plan to improve fuel consumption ratings: transparency from carmakers, independent testing to better reflect ‘real world’ conditions and compulsory standards for fuel efficiency and engine emissions.
“The Federal Government needs to establish a process to ensure vehicles imported to Australia comply with the regulatory requirements - currently, certification is based on assurances from manufacturers that the vehicles comply,” NRMA’s Jack Haley said.
Claimed fuel figures from carmakers are certainly possible on the road - TMR has proven it with Volkswagen’s Think Blue Challenge - but the effort required to do so is excessive, to say the least.
Senator Nick Xenophon To Push New Legislation
Independent South Australian Senator, Nick Xenophon, has also called for change to ensure accurate fuel consumption figures for Australian motorists.
Senator Xenophon has echoed most of the NRMA’s calls, but added that carmakers should face fines of up to AU$50 million for “wildly inaccurate” claims - even as low as 10 percent beyond the official figure.
If the figure is consistently outside the 10 percent window, Senator Xenophon said carmakers should be forced to pay compensation to its owners.
“Car companies can use artificial test conditions, including taking out the back seats to make the car lighter or switching off features like air conditioning to make inaccurate fuel economy claims,” Mr Xenophon said.
“Testing for fuel economy can be difficult, but the gaps between what is advertised and what is actually achieved on the road really does stretch the credibility gap. Motorists have been treated like mugs for too long. A family could typically be many hundreds of dollars a year worse off from what they budgeted for because they’ve been misled into buying a particular car.”
Senator Xenophon will release an exposure draft of the Bill this month.
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