A Calgary couple is accusing General Motors of misleading them after they bought a Chevy Cruze that they said guzzles 50 per cent more gas than the automaker advertised.

“I strongly feel cheated,” said vehicle owner Farah Mocquais.

“We didn’t save any money — quite the opposite,” said her husband Pierre-Yves.

He estimates they will spend $3,500 more on gas than they banked on by the time the odometer reaches 100,000 kilometres, solely because of lower fuel efficiency than promised.

Farah is the primary driver of the Chevy Cruze LT 1.4L, which the couple bought new in 2011. (CBC)

“We know that in most cases the [fuel efficiency] tests are done under specific conditions,” he said. “But this was really grossly different.”

The couple bought their Cruze LT 1.4L automatic new in 2011, based on GM’s figures that the car would burn 5.5 litres of gas every 100 kilometres of highway driving.

They said they bought the second car so Farah could commute by highway to her job in Lethbridge, which is two and a half hours each way.

“We wanted something that would allow her to go between the two cities in a manner that would be really responsible in terms of fuel consumption,” said Pierre-Yves.

Highway driving only

Over the next several months, the couple said the car was driven 99 per cent on the highway, but the fuel consumption display screen consistently showed it used 8.5 litres per 100 kilometres.

The number improved slightly over time, they said. When a CBC News camera went along for a recent highway drive, the screen in the 2011 Cruze displayed a fuel consumption rating of 7.9 litres.

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That's still 2.4 litres more gas consumption than GM’s rating, for every 100 kilometres Farah drives.

“[The dealership] hooked the car onto all sorts of measuring devices and so on and so forth and at the end they told us there was nothing they could do,” said Pierre-Yves, who said Jack Carter Chevrolet then suggested he complain to the automaker.

Mocquais emailed GM Canada and sent a complaint by registered letter, but said he heard nothing back.

“General Motors completely ignored it, ignored emails and ignored registered letter with the documentation,” he said.

A GM Canada spokesperson said the company called Mocquais, but didn’t reach him.

“We continue to reach out to him to discuss his inquiry. We take our customer concerns very seriously and will work directly with Mr. Mocquais to determine how we can assist him further,” said Adria MacKenzie.

Tests show discrepancy

When a CBC News camera went along on a highway drive, the fuel consumption display showed 7.9 litres of gas used for every 100 kilometres. The couple said, until recently, the gauge was consistently showing 8.5 litres. (CBC)

Consumer Reports in the U.S. recently cited the 2014 Chevy Cruze and other North American cars for relatively poor gas mileage.

Its independent tests showed the 2014 Cruze with a 1.4 litre engine used the equivalent of 9.05 litres of gas per 100 kilometres in combined city/highway tests, which is one third more than the combined city/highway results that GM Canada claims.

GM Canada’s spokesperson said many factors can change fuel consumption results.

“Several factors can affect fuel use: driving style and behaviour, vehicle acceleration and driving speed, overall age and operating condition of your vehicle, temperature, weather, traffic, road conditions and drive systems and powered accessories (i.e. air conditioning) installed in your vehicle,” said MacKenzie in an email.

“There is also a break-in period for new vehicles to determine accurate fuel consumption.”

GM is not the first carmaker to come under fire for misleading figures. The maker of Hyundai and Kia vehicles is reimbursing customers millions of dollars, after the U.S. Environmental Protection Agency determined its fuel consumption test results had been inaccurate.

Canadian tests panned

Canadian government-approved tests have been panned by critics for several years, for not being as realistic as U.S. tests done by the same automakers there.

GM's sales material said the couple's car would average 5.5 litres of gas for every 100 kilometres of highway driving. (CBC)

“The lack of government oversight results in a flawed test procedure and the government is allowing the carmaker to hide behind it,” said George Iny of the Automobile Protection Association.

“It would be better to let the carmakers carry the can on their own for this, because at least you could sue them.”

NDP consumer affairs critic Glenn Thibeault suggests the competition bureau should be looking into possible misleading advertising, because that is its mandate.

“Right now we have a toothless tiger when it comes to the competition bureau,” said Thibeault.

“If we had organizations like the competition bureau with the necessary resources to do these investigations, companies would then know that they can’t just put up a number that they think they can put up there to sell more cars, if that is what they are doing.”

Government to bring in better tests

The Competition Bureau said it does not disclose what, if anything, it is investigating about fuel consumption advertising or anything else.

However, Natural Resources Canada, which governs the tests and results car makers use for their advertising, said it will soon announce changes that will bring Canadian tests in line with U.S.

NDP Consumer Affairs critic Glenn Thibeault believes the federal competition bureau should investigate fuel efficiency advertising by automakers. (CBC)

“The resulting new approach will provide Canadians with fuel consumption ratings that better reflect ‘typical’ driving conditions and driving behaviour,” said spokesperson Jacinthe Perras.

GM said it expects the new tests to be in place for 2015 models.

Critics say that is good news for consumers contemplating future purchases, But they point out it also essentially confirms that, up until now, thousands of Canadian consumers have been misinformed.

“All of us are basically impotent in front of the actions of, on the one hand, big corporations and on the other, government,” said Pierre-Yves.

“Somehow this type of misleading advertising has to stop.”

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