RAY: Ha! We're back. You're listening to Car Talk with us, Click and Clack, the Tappet Brothers, and we're here to discuss cars, car repair and, uh, the new Puzzler. And I've got to say that I like this one because it's automotive. We haven't had an automotive Puzzler in a while. I heard the clamoring about that. And, more than that, this actually was sent to us pretty recently.

TOM: This year?

RAY: This decade.

TOM: Decade!

RAY: This comes from someone named Brad Hamill. Here it is. I really can't improve it much, so I'll just read it and you guys will have to figure it out.

TOM: All right.

RAY: This fellow takes his Volvo to the shop. Now, it could be any car. And complains of a strong pulsing in his brake pedal when he applies the brakes. The mechanic looks over the car and finds that, sure enough, the front disc brake rotors are warped.

TOM: Yeah.

RAY: He installs new ones and sends the fellow off on his way. Five thousand miles later, the same car owner comes back to the shop and complains that the pulsing is back.

TOM: Oh!

RAY: Suspicious and yet confident that his work was perfect, the mechanic asks the owner a few questions. "Do you ride the brake? Have you tightened your lug nuts with a high-powered air wrench, or has anyone done that?"

TOM: Mmm.

RAY: Et cetera. "Have you bought new tires?" The owner answers no to all questions. In fact, he answers no all the time to everything. The mechanic is at a loss and replaces the warped rotors.

TOM: Yeah.

RAY: A thousand miles later, the guy comes back, and guess what? He has an oil leak this time. But a thousand miles after that, he comes back with the same problem. This time, the mechanic asks straight up what the heck he's doing to the car that could be causing this problem, knowing that there's nothing wrong with the parts and nothing wrong with the installation.

TOM: Mmm-hmm.

RAY: The fellow says, "I don't know." He says, "I go on a lot of long car trips, and it's always the day after I arrive home from these trips that I start feeling the pulsing, but never..."

TOM: Oh!

RAY: "Never during the trip."

TOM: This is great!

RAY: The mechanic asks him one question.

TOM: Yeah.

RAY: And he knows the answer to the puzzle. What question did he ask him?

TOM: What does your mother-in-law weigh?

RAY: All right. He asks him two questions. Now, if you think you know the answer, write it on the back of a $10 bill or a stale gingerbread man--something that's been hanging on your tree for a few weeks.

TOM: Ah, sure! Festive!

RAY: And send it to Puzzler Tower, Car Talk Plaza, Box 3500, Harvard Square, Cambridge.

TOM: Our Fair City.

RAY: MA 02238. Or you can e-mail your answer from the Car Talk section of cars.com. If you'd like to call us, you didn't ask any questions along the way. You felt it didn't require any further...

TOM: No. I thought it was perfectly clear.

RAY: All right.

TOM: And there was very little obfuscation going on.

RAY: I didn't get a chance to obfuscate.

TOM: And I didn't feel it necessary to call you to task.

RAY: Really!

TOM: I didn't.

RAY: Wow! Gee, how unfortunate. I'll remedy that by next week.

TOM: Did you sneak something by me?

[ Car Talk Puzzler ]