Editor's Note: This is an updated version of an earlier story, also reported on "Good Morning America," to correct a calculation error. See details of the correction below.
A survey of the major rental car companies by federal safety officials found that in a significant number of cases the companies have rented cars under safety recall without first fixing the defects.
According to the survey, commissioned by the National Highway Traffic Safety Administration (NHTSA), the big three in the rental car business -- Hertz, Enterprise which owns National and Alamo, and Avis/Budget – since 2006 have let tens of thousands of drivers go on the road without repairing defects.
Due to a calculation error by ABC News, an earlier version of this story, also reported on "Good Morning America," misinterpreted the data on the percentage of repairs and did not give the rental car companies all the credit they were due. Even so, safety advocates say anything short of a 100 percent repair rate is unacceptable.
"The bottom line shows that none of the rental car companies are doing a good job," Clarence Ditlow, executive director of the Center for Auto Safety, told ABC News.
Last November, NTSHA had asked the domestic car manufacturers to provide recall repair information from the car rental companies because of "incidents involving allegations of personal injury and death" allegedly caused by "safety defects" on rental vehicles.
The best overall performance came from Enterprise. In a study of 10 General Motors and Chrysler recalls between 2006 and 2010, after 90 days, Enterprise had fixed an average of 65 percent of the cars subject to the recall.
For Avis/Budget, 53 percent of the cars were fixed . At Hertz, only 34 percent of the cars rented 90 days after a recall had been fixed.
The NHTSA study came after ABC News reported on "Good Morning America" last July on the deaths of the Houck sisters of California, 24-year old Raechel and 20-year old Jacquie, who were killed in an accident involving their Enterprise rental car. The car they were driving was a Chrysler PT Cruiser, one that a month earlier had been recalled because a possible leak in the power steering fluid could "result in an under hood fire."
The Houck's car was never fixed. Raechel and Jacquie died instantly after the PT Cruiser caught fire and hit an oncoming semi-tractor trailer on Highway 101 in Northern California. The sisters had rented the car in Santa Cruz, Calif., to visit their parents in Ventura County.
"We found out that they had rented this same car three times in that month period before they rented it to Raechel and Jacquie," Houck's family lawyer, Larry Grassini, said.
The Houcks sued Enterprise, and after a lengthy legal fight, the company admitted negligence and was required to pay $15 million in damages to the family. Now, the girls' mother Cally Houck is pushing the California legislature to pass a law requiring rental car companies to ground all recalled vehicles until they are fixed. Citing the Houck case, the Center for Auto Safety has also petitioned the Federal Trade Commission to require Enterprise to fix vehicles under recall before renting them out.
"I do not want another family to have to go through this type of ordeal," Cally Houck said.