By Gabe Nelson, Crain News Service
WASHINGTON (Aug. 26, 2013) — Don't blame the test.
That's the message from the U.S. Environmental Protection Agency (EPA) in the wake of Ford Motor Co.'s decision to restate fuel economy estimates on its C-Max Hybrid.
When Ford C-Max owners were griping about worse-than-promised fuel economy last year, the conventional wisdom was that the EPA tests couldn't reliably measure the performance of hybrid cars.
Consumer Reports magazine stoked the fires, claiming that half the hybrids it tested fell short of their advertised mpg numbers by 10 percent or more. Ford chimed in as well, saying it would help the EPA figure out whether its tests were inflating the fuel economy estimates for many hybrids.
It was enough to make the EPA's own engineers question the accuracy of their tests, said Christopher Grundler, the agency's top auto industry regulator. But this summer, when the EPA ran the Toyota Prius and Hyundai Sonata hybrids through the same battery of tests that tripped up the C-Max, the other hybrids did fine.
"It was all quite reassuring," Mr. Grundler told Automotive News. "The problem here is really not how the testing is done."
Ford doesn't seem convinced.
"This is an industrywide issue with hybrid vehicles," Raj Nair, the head of global product development for Ford, told reporters this month in announcing the C-Max restatement. "We've learned along with EPA that the regulations create some anomalies for hybrid vehicles under the general label rule."
According to the EPA, the C-Max had an inflated combined fuel economy estimate of 47 mpg because Ford used test results from the more aerodynamic Fusion Hybrid, which shares a powertrain with the C-Max and weighs about the same.