The van burst into flames while parked right in his driveway! Turns out Bob's van was one of 98,000 recalled because of a wiring defect that could cause a fire. The used car dealer Bob bought it from never told him it had an unfixed recall.

"The whole thing was a complete loss for me," Bob recalls.

A study by Carfax found more than 2.7 million used vehicles listed for sale online last year had at least one unfixed safety recall. How serious is it? The federal government doesn't recall cars unless a defect could cause a serious risk.

Clarence Ditlow works for the Center For Auto Safety. "They're all serious. They could cost you your life. They could cause a crash," he warns.

Undercover cameras at used car lots easily found vehicles for sale, that according to car manufacturer websites, have unfixed recalls:

'A used SUV has an unrepaired defect which could make the engine stall and cause a crash.'

Another used car also has a dangerous unfixed defect: 'The engine could shut off while the vehicle 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 it today and may in fact go to another used car dealer and buy a different vehicle," Ditlow explains.

There's no federal law requiring used car dealers, or private sellers to tell buyers about unfixed recalls. The two main used car dealer trade associations would not appear on camera.

But the National Independent Automobile Dealers Association says it: "Encourages used vehicle dealers to repair the open-recall before selling the vehicle to a customer… and at a minimum disclose it…"

Experts say some dealers do go the extra mile.

Jeannine Fallon works for Edmunds. She says, "Many dealers will bring a used car up to speed on its recalls before they sell it and actually if they do it's a sign they take really good care of their cars and really good care of their customers."

The other used car dealer association says the onus is on vehicle owners and used car buyers to get recalls fixed: "To improve safety, the National Automobile Dealers Association urges vehicle owners to have recalled vehicles fixed as soon as possible."

Bob says he now wants to warn others. "What happened to me, it could have happened to someone else."

If you have your car's vehicle identification number, or VIN, you can simply pick up the phone and call your local dealer to see if you have any unfixed recalls. Carfax and the Center For Auto Safety's websites allow you to enter your VIN and check for open recalls online. Dealers repair recalls for free, and getting recalls fixed could save your life and also help prevent your car from being sold to a future buyer with a dangerous defect.