You can look under the hood all you want, but chances are you will never find the problems on some used cars for sale all over the country.
A charred, burnt-out shell is all that remains of the used van Bob Knotts bought.
"It was just black, full of smoke," Knotts said.
The van burst into flames while parked right in his driveway. It turns out the van was one of 98,000 recalled because of a wiring defect that could cause a fire. The used car dealer never told Knotts the van had an unfixed recall.
"The whole thing was a complete loss for me," Knotts said.
The problem is bigger than one van.
Carfax found more than 2.7 million used vehicles listed for sale online last year had at least one unfixed safety recall.
"They're all serious. They could cost you your life, they could cause a crash," said Clarence Ditlow with the Center of Auto Safety.
We found a used SUV has an unrepaired defect which could make the engine stall and cause a crash. And we found another car that has an unfixed defect that could shut the engine off while it is being driven.
"They don't want to take them off their lot to get them fixed before they sell them because that customer is ready to buy today and may in fact go to another used car dealer and buy a different vehicle," Ditlow said.
There is no federal law requiring the disclosure of unfixed recalls. Some dealers fix recalls before sale, but not all, so it's up to consumers to find out for themselves.
"What happened to me, it could happen to someone else," Knotts said.
There are easy ways to check on open recalls. Carfax has a free recall check, and on the Center of Auto Safety's website, a car's vehicle identification number to see if the car has an unfixed recall.