Audi has been rapped by advertising chiefs for 'misleading' claims that its Audi A3 TDI model could do 68.9 miles per gallon (mpg). Motoring writer Maria McCarthy takes a look.
Motorists in the know are aware that there's a difference between the fuel economy rates a car manufacturer might advertise and what you would get in everyday driving.
This is because official figures are based on EU standard test procedures which don't bear much resemblance to motoring in the real world.
They are often conducted under lab conditions, and items that consume fuel, such as air conditioning and heated rear windows, are all turned off.
However, a recent case against Audi brought to the Advertising Standards Authority (ASA) may change this.
The ASA ruled that car manufacturers have to make it clear to motorists that they are unlikely to achieve the same levels of fuel economy in real life as in test conditions.
This followed an online advert for an Audi A3 TDI which read, "Audi A3 TDI - the most fuel-efficient Audi ever".
The advert went on to state that the motor was capable of 68.9 miles per gallon (mpg).
The ruling didn't question the test figure, but instead judged that the manufacturer did not properly explain that it was achieved under laboratory conditions and may not be possible for the ordinary driver.
A duty to inform consumers
Audi defended itself by saying fuel consumption and emissions figures needed to be tested under EU standardised procedures.
This is to ensure that different makes and models could be compared against each other.
Audi also claimed the fact that test results usually resulted in higher mpg figures was well known to consumers.
However, the ASA disagreed and said that while some consumers might be aware of this, others weren't and the company had a duty to inform them.
'Important to clarify matters'
Dave Richards, editor of Classic Car Weekly and a former mechanic, agrees.
"Not everyone takes an interest in motoring news and issues," he said.
"Many potential buyers might not realise that they wouldn't be able to achieve the advertised mpg, so it's important for manufacturers to clarify matters.
"Unless you're a very skillful driver who knows how to drive with a featherweight right foot and focus on keeping momentum once it's gained, you stand no chance of getting within 20 per cent of the manufacturer's mpg data."
Real world fuel consumption
Fuelly is a website which allows you to both track your own mileage and fuel expenses and also to check out how other motorists are doing.
Richards added: "If you want a real world idea of the consumption of the type of car you're going to buy, log on to Fuelly to see the consumptions others are getting from the cars you're interested in."
To work out how much you're spending over time and budget for your fuel, you can also use Confused.com’s handy fuel price calculator.
So, with different sources of advice on possible mpg available, the tip for canny motorists is to be sceptical of manufacturer's optimistic claims and do your own research before buying a new car.
With budgets tightening and fuel costs rising, it'll be time well spent.
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