Fuel Economy Faux Pas

By Tom Ripley

No, it isn't just you.  If you are disappointed that your car doesn't get the gasoline mileage that its Environmental Protection Agency sticker says it will get, you are not alone.  After lengthy rounds of tests, Automobile Club of Southern California and AAA car review experts have come to the same conclusion as many motorists -- the actual miles per gallon achieved during the daily use of a vehicle generally falls well short of Environmental Protection Agency (EPA) estimates. And further, they have test drive data to support that contention.  The AAA driving tests found dozens of examples where vehicle miles per gallon of 2003 and 2004 model year vehicles were overestimated because of what AAA has referred to as "outdated 30-year-old EPA tests."

"New car buyers soon see that their experience with mileage often falls short of EPA estimates," said Steve Mazor, principal automotive engineer. "It's not a case of `your mileage results may vary'. We know that, in most cases, `your results WILL vary'."
 
The current EPA tests were established in the late 1970s and do not take into account higher speed limits on many interstates and increased congestion nationwide. And they fail to address many real-world issues.  For example, the tests are conducted with air conditioners off.

AAA admits that its test drive data is "neither standardized nor scientific," yet it asserts the data may be more meaningful to consumers than the EPA numbers as they make car-buying decisions.  The organization doesn't suggest that its numbers take the place of the current EPA reports.  But it does suggest that the current system be fixed. 

Data released by AAA seems to reinforce that notion.  For example, a mainstream vehicle like the 2004 model year Toyota Corolla carried an EPA mileage rating of 32 miles per gallon in the city and 40 mpg on the highway, but AAA opined that 28.9 mpg is a better estimate.  Similarly, a 2004 Chevrolet Trailblazer with an EPA rating of 15/21 garnered an AAA mileage prediction of just 13.6 mpg.  In all the study examined cited the federal mileage estimates for 75 commonly available vehicles and found the EPA estimates were inaccurate for every one of them.

"We believe consumers should have the most accurate information possible when it comes to expected gas mileage of the vehicles they purchase," said Mazor. "This would be accomplished by requiring EPA to use 'real world' tests in setting federal mileage estimates."   

To that end, the "Fuel Efficiency Truth-in-Advertising Act of 2005," which would require EPA to update its miles per gallon testing procedures, has been introduced in Congress and has gained AAA backing.  The legislation has bipartisan support in the United States Congress and is sponsored by U.S. Representative Nancy Johnson (R-CT) and U.S. Representative Rush Holt (D-NJ).

However, unless the legislation offers auto manufacturers relief from the government-mandated Corporate Average Fuel Economy standards, which dictate minimum standards for overall fuel economy, you can bet the proposal will be fought tooth-and-nail by auto manufacturers.  Despite the perception of "high" gasoline prices, many manufacturers are struggling to meet those fuel efficiency bogeys in light of consumer preference for bigger, more powerful vehicles.

Formerly based in Boston, Tom Ripley now covers the auto industry and the human condition from his home in Villeperce, France.