TOM: Since the two big hurricanes, we've had a flood (ha ha) of questions about flooded cars. So we thought we'd try to answer the most common questions:

* How do you know if a car you're buying has flood damage?

TOM: You might see mineral deposits or discoloration on the seats, seat belts or door panels. There may be droplets of moisture on the inside of the instrument cluster, warped or misshapen door panels (if they're made of fiberboard), or an owner's manual that looks like it fell into a bathtub. But most likely, if a "professional" is trying to pass off a flooded car on the used-car market, he will have cleaned up all those things, and perhaps even replaced the seats and carpet. It will be very difficult for the average buyer -- or even the average mechanic -- to be able to tell that the car was flooded.

RAY: So, our best advice is to simply avoid used cars that have come from flooded areas. Unfortunately, flooded and salvaged cars can be re-registered in other states with clean titles, and then sold without disclosing the damage. That's called title washing.

TOM: Your best bet is to use a service called Carfax. We've put up a link to it on our Web site, It offers a free service that will check the Zip code in which a car was last registered, and will let you know if it was registered in one of the flooded areas. You need the vehicle identification number, or VIN, to get a report.

RAY: While it's not absolutely perfect (it's possible that someone with a car registered elsewhere could have driven to New Orleans and been there for the flood), that's about the best chance you have to spot a potentially flooded car before you buy it.

* Is a flooded car necessarily junk?

TOM: Pretty much, yes. There are some obvious problems, as you can imagine. If water gains access to one of the cylinders, either through the air intake or the exhaust system, that cylinder can fill with water. Then, when the engine is started, that cylinder will hydro-lock (water can't be compressed the way air can), and everything connected to the cylinder will break or bend.

RAY: But even if the water is pushed out safely before the car is started, that cylinder has already had water sitting in it for a week. Those cylinder walls and rings are probably already rusting. So that engine's going to burn oil like crazy and run unevenly.

TOM: Water can get into the transmission through the transmission-fluid dipstick hole. If that happens, you'll be lubricating the transmission with one part transmission fluid and two parts water, or something like that. So kiss the transmission goodbye, too.

RAY: Inside the car, lots of manufacturers now put electronic components -- such as computers -- under the seats, or under the dashboard. So even if only a modest amount of water was sloshing around the floor of the car, you may need a new computer -- or several new computers, depending on your car -- which can cost $1,000 each.

TOM: We'd say if water got any farther than the floor of the car, it's junk.

Got a question about cars? Write to Click & Clack in care of The Post, or e-mail them by visiting the Car Talk Web site at

(c)2005 by Tom and Ray Magliozzi

and Doug Berman