Dear Tom and Ray:

My wife keeps telling me this is happening, and I want to believe her, but the local Chrysler dealer and our favorite mechanic are stumped. Every two or three weeks, my wife will be driving her 1998 Chrysler Town and Country LXi when the front brakes slowly start to apply themselves. No matter how much she presses on the accelerator, the car eventually won't move an inch. It's happened three times. By the time she stops, smoke is pouring from the brakes. An hour later, the car will run fine again. Mechanics have replaced both of the front brake lines, saying the lines were semi-clogged. But we're still having the problem. What's wrong?

-- Paul

RAY: Well, first of all, Paul, you should always believe your wife when she tells you something is wrong with her car.

TOM: I learned that the hard way. My wife was complaining that her old Volvo wagon was acting up. She couldn't make it happen with me in the car, so I told her she was dreaming. She said: "Fine. You drive it." A couple of days later, after it died on me in a torrential rainstorm, I walked the 2 miles home, entered the house soaked all the way down to my mutandis, and said, "OK, I believe you, hon."

RAY: Well, I'm not surprised that replacing the brake lines didn't fix it. After all, what are the chances that two independent brake lines just happened to go bad at the same time? My guess, Paul, is that your wife's car has a bad power-brake booster.

TOM: The booster uses vacuum to amplify the pressure that your foot puts on the brake pedal. Sometimes when boosters go bad, they "stay on." So, it's as if you never took your foot OFF the brake pedal last time you stopped. And each time you use the brakes, the pressure increases, until the vehicle can't move.

RAY: And then there's smoke pouring out from the brakes from all the friction. Don't forget about the smoke. Smoke's very exciting.

TOM: So, I'd ask your mechanic to try a new power-brake booster. It's also possible that there's something wrong with either your antilock braking system or the master cylinder itself. But I'd try the booster first.

RAY: Actually, I'd apologize to your wife for ever doubting her, first, Paul, and try the booster second.