A dangerous scam that hides major problems with used cars is on the rise. According to new research from Carfax, nearly 800,000 used cars lurking on America’s roads right now may be part of an emerging fraud called title washing. What’s also alarming is that more than 500 are likely being used as taxis. Consumers in New Jersey, North Carolina, Mississippi, California, and Georgia are most at risk, but thousands of title washed cars are in every state.

Title washing makes rebuilt wrecks and cars with odometer issues look like problem-free used cars on paper. Professional con men illegally alter vehicle documents to get title brands such as ‘salvage’ or ‘flood’ removed from a car’s title. They’ll often patch up the wrecked cars, move them to other states and sell them with a clear title to unsuspecting buyers. Victims can lose thousands and put their lives at risk purchasing used cars with washed titles.

“Our research is clear evidence that title washing continues to fly under the consumer’s radar,” said Larry Gamache, communications director at Carfax. “These cars are sold mainly by perfect strangers who bank on you not taking the proper steps to protect yourself. Demand more information than just the car’s title from any seller and shop at places where vehicle history information is readily available, like the all-new Carfax.com. Knowing what you buy and who you buy from are equally important to help avoid dangerous schemes like title washing.”

Every Motor Vehicle Department in the U.S. and Canada reports branded titles to Carfax. With this information, consumers get unprecedented protection from Carfax to help identify and avoid hidden problems. Car buyers and sellers can rest assured they’ll know about reported title brands under the exclusive Carfax Buyback Guarantee. Plus, Carfax Vehicle History Reports alert people to cases of potential title washing. An inspection by a certified, trusted mechanic is also recommended before buying any used car.

Titling laws can differ from state to state. To help, Carfax offers consumers a Used Car Buying Guide with free information about car titling and used car scams, as well as tips to help purchase safe reliable used cars.