The issues began when Consumer Reports magazine questioned Ford's mileage claims for their hybrid models, specifically their electric Ford C-Max.
The magazine said some of Ford’s line-up didn’t deliver the anything near what kind of gas efficiency advertised.
Now the EPA says they will test the next generation C-Max hybrid and then reevaluate their own rules for determining mileage.
Normally the agency has allowed car manufacturers to test and publish gas mileage as long as they stuck to EPA rules. The feds then re-check about 15% of those claims to be sure they are accurate.
In this case the agency thinks driving habits and conditions greatly affect the mileage these cars get.
Ford says they are fine with the extra testing.