Missouri was in the top five states with used cars for sale online that had unfixed open recalls, according to a 2013 Carfax report.
The company, founded in Columbia 30 years ago, conducted the survey last year and said Wednesday the numbers put Missouri at number three nationwide.
Across the country, Carfax found 3.5 million vehicles for sale online with unfixed recalls.
"The most concerning thing is that about one third of all recalled cars don't get fixed," said Carfax public relations manager Christopher Basso. "What we've seen in the last three weeks will just add to that total number of recalled cars out there, up for sale, and being driven every day."
General Motors has recalled more than six million vehicles this year, more than two million because of a flaw in the ignition switch that has been blamed for 13 deaths. The company CEO spent this week getting blasted by lawmakers, including Missouri Senator Claire McCaskill, on Capitol Hill.
"There is nothing that says a seller has to disclose or fix an open recall for a used car," Basso said.
In Columbia, several smaller pre-owned car dealers said Wednesday they did not keep track of open recalls on cars in their lot.
A manager at Regal Car Sales and Credit showed ABC 17 News an internal system the company uses to track vehicles it has with open recalls.
"Our company doesn't allow us to sell a vehicle until the recall has been cleared up," said Regal manager Jacob Schneider.
Several websites allow would-be buyers to check a car's Vehicle Identification Number (VIN) for open recalls, including Carfax. Pre-owned car sellers said that was the most reliable way to check, aside from taking the vehicle to the dealership.
"The most important thing about recalls is knowing that there is one so you can do something about it," Basso said. "Unfortunately, a lot of people aren't looking at recalls."
On Wednesday, Chrysler announced the recall of more than 800,000 Jeep Grand Cherokees and Dodge Durangos because the booster could corrode and make the brakes hard to use.