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#0938: How Many Lightbulbs Does it Take to Screw up a Relationship?

Original Air Date: 09.19.2009

   Best Moment

Description: 
This week on Car Talk, the Great Kerhonkson, New York's Headlight Debate. If one headlight bulb burns out on your car, do you need to replace the other one at the same time, even if it's still shining brightly? Maria says one is enough, but her boyfriend is a two-timer. Find out where Tom and Ray come down on this burning (sorry) issue. Meanwhile, Zach in Oregon has become a dry cleaner's best friend. His Civic is leaving unsightly brown stains on his passengers' pants. Also, a Mercury fights back after becoming a Cash for Clunkers candidate, a trip to Blockbuster becomes more death defying than the latest Indiana Jones movie, and how do you handle a backward headrest? All this, plus Opening Day for the new Puzzler season, this week on Car Talk.

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This Week's Puzzler

Tommy flies, and walks, from One Horse, Nevada to the nearest town. Would the trip have been longer, shorter, or the same length of time, if he had just walked? Find out!

Last Week's Puzzler

No puzzler answer this week-- the puzzler returns from vacation.

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Reasoning why we replace both headlights

by mike

This is one of the many obsessive disorders that the human race seems to grasp. The rule to eliminate total confusion, when something is modified or changed is to keep it as close to the original as possible. example: Electronic cameras have a electronic circuitry embedded in it that creates a "clicking sound" similar to the old fashion cameras. Nobody would buy them without it. As for the headlights, years ago the service station used to replace the units, sometimes refocusing the beams. Since the vehicle was being worked on, it was easier and less expensive to do both lamps. (One service call bill instead of two) The average person back then didn't want to be bothered with this tasks. Thus this has lodged in peoples minds that both be replaced at the same time.

get a heavy duty h7 bulb

by Anonymous

get heavy duty h7 bulbs from Roger Beasley Volvo in Austin, TX 512-452-0266. This is a standard Volvo part. David Hoge wd5fgz@arrl.net

Memoryless Property

by mathwhiz

I'm surprised no one has commented on this. I just listened to the podcast of this show and can shed some light on the question of whether you should replace one headlight or two. Reliability theory tells us that the mean time to failure for a light bulb follows the exponential distribution, which has the memoryless property. The memoryless property states that even if we know how long the light bulb has lived so far, the mean time until the bulb fails will not have changed - that is, knowing how long the bulb has lasted doesn't tell us how long the bulb will last. So both headlights should not be changed at the same time because the other could have a long life left!

relamping

by peter kennedy

I am an electrical engineer and just want to weigh in on the topic of changing one headlamp or two. It is true that some commercial bulidings change all of the lamps at the same time. But, this is because of the labor cost of relamping. Ladders or other scaffolding is used to position the workmen so they can safely do their job. This 'overhead' cost is minimized by changing all of the lamps on a predetermined schedule. For a automotive headlamps, it is more economical to change the lamps as nedded.

Favorite Moment: I enjoy your entire show!

Close but no cigar!

by Media Bill

Ray and Tom: This morning as I was listening to your show on WHYY in Philadelphia (yes, I am a member!) I heard you give some advice to a budding novelist who needed to have a way for her protagonist to disable her older car with a V8 engine (I didn't catch the make, model or year)in such a way that no one could start it while she was away and she could re-start it when she returned. You gave her the simple expedient of removing the coil wire. This will make the car incapable of being started in that state BUT (wait for it...) anyone with even a modicum of car-knowledge (such as you guys!) could easily make a short-term patch that would enable you to drive off without any special tools or equipment. Simply remove one of the 8 spark plug wires (the shortest one preferably), remove the rubber boot from the spark plug connection and jam it into either the coil or the distributor and the other end into the other terminal opening. Now it won't run well, but I know for a fact that even a 6 cylinder engine (during a road trip in my 1960 Ford Falcon in Austria while enjoying an all-paid world tour in a green uniform) will run with one spark plug not firing and a V8 would run even better. If the car is of a 1960 or earlier vintage, the better solution (albeit requiring a bit more specialized knowledge on the part of the protagonist) is to pop the distributor cap (usually easy to get at on a V8 and generally requiring only strong fingers or a flat blade of some sort to pop off the snap clips) and remove the rotor. It's smaller to carry in the purse and cannot be easily replaced with any other readily available part. Love your show guys! Keep on truckin'! Bill

Crazy Lady Drives Volkswagen thru Blockbuster...

by davidbuick

While I was amused by the VW story, I was very distressed to listen to Tom and Ray who accomodated this lady with her ridiculous story while overlooking the most obvious and only physical possibility of the unintended acceleration. The lady blamed the cruise control; however, there is no cruise control system on earth that disables the brakes. To the contrary, in any car including VW if the brake pedal is firmly depressed, then the car will not lurch or go or move. If a car crashes throuh a storefront during a parking manuever, the only possible explanation is that the driver of the car accelerated. If she had her foot on the brake as she claims she did, then the cruise control could not have possibly moved the car. Audi had a problem with foot pedal placement 20 years ago which was the only reason for their unintended acceleration problem. I don't think that the pedals are in bad spots in this VW. And while the cruise control may cause the car to lurch a little while driving, there is no way that cruise control would disable the brakes and cause someone to move while the brakes are firmly depressed. I wish that this message was clearly discussed, but it was not.

Favorite Moment: The best was last. The lady who called in about disabling the 58 Olds was great. I want to read her book. And the answer was ingenius. I'll remember that.

Reasoning why we replace both headlights

by mike

This is one of the many obsessive disorders that the human race seems to grasp. The rule to eliminate total confusion, when something is modified or changed is to keep it as close to the original as possible. example: Electronic cameras have a electronic circuitry embedded in it that creates a "clicking sound" similar to the old fashion cameras. Nobody would buy them without it. As for the headlights, years ago the service station used to replace the units, sometimes refocusing the beams. Since the vehicle was being worked on, it was easier and less expensive to do both lamps. (One service call bill instead of two) The average person back then didn't want to be bothered with this tasks. Thus this has lodged in peoples minds that both be replaced at the same time.

Responses to Lousy Pick Up Lines

Guaranteed to work for anyone!

A Woman and a Man Meet on a Train

Headed toward Cleveland at 63 mph, and... oh, wrong joke.

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