View Full Version : even insane-looking problems are sometimes real.

19-05-2002, 07:48 PM
For the engineers among us who understand that the obvious is not always the solution, and that the facts, no matter how implausible, are still the facts ...

A complaint was received by the Pontiac Division of General Motors:

'This is the second time I have written you, and I don't blame you for not answering me, because I kind of sounded crazy, but it is a fact that we have a tradition in our family of ice cream for dessert after dinner each night. But the kind of ice cream varies so, every night, after we've eaten, the whole family votes on which kind of ice cream we should have and I drive down to the store to get it. It's also a fact that I recently purchased a new Pontiac and since then my trips to the store have created a problem. You see, every time I buy vanilla ice cream, when I start back from the store my car won't start. If I get any other kind of ice cream, the car starts just fine. I want you to know I'm serious about this question, no matter how silly it sounds: 'What is there about a Pontiac that makes it not start when I get vanilla ice cream, and easy to start whenever I get any other kind?''

The Pontiac President was understandably skeptical about the letter, but sent an engineer to check it out anyway. The latter was surprised to be greeted by a successful, obviously well-educated man in a fine neighborhood. He had arranged to meet the man just after dinner time, so the two hopped into the car and drove to the ice cream store. It was vanilla ice cream that night and, sure enough, after they came back to the car, it wouldn't start.

The engineer returned for three more nights. The first night, the man got chocolate. The car started. The second night, he got strawberry. The car started. The third night he ordered vanilla. The car failed to start.

Now the engineer, being a logical man, refused to believe that this man's car was allergic to vanilla ice cream. He arranged, therefore, to continue his visits for as long as it took to solve the problem. And toward this end he began to take notes: he jotted down all sorts of data, time of day, type of gas used, time to drive back and forth, etc.

In a short time, he had a clue: the man took less time to buy vanilla than any other flavor. Why? The answer was in the layout of the store.

Vanilla, being the most popular flavor, was in a separate case at the front of the store for quick pickup. All the other flavors were kept in the back of the store at a different counter where it took considerably longer to find the flavor and get checked out.

Now the question for the engineer was why the car wouldn't start when it took less time. Once time became the problem -- not the vanilla ice cream -- the engineer quickly came up with the answer: vapor lock. It was happening every night, but the extra time taken to get the other flavors allowed the engine to cool down sufficiently to start. When the man got vanilla, the engine was still too hot for the vapor lock to dissipate.

19-05-2002, 10:25 PM
As a mechanic I was fascinated by this story and at the beginning thought that this was leading to a 'punch line'. What an amzing story.

This reminds me of another (although no where as bizarre) story about a little old lady who had a wee morris 1300. She would constantly complain to her mechanic that the car worked perfect except when it warmed up then it would run rough. The mechanic duly checked the car over and found nothing wrong. The car would go back and sure enough she would be back the next week with exactly the same problem. Absoulutely everything inlcuding carburettor, spark plugs air filters the lot. But always the same result the car would start fine in the morning but shortly after run rough.
After several weeks of this the mechanic had had enough and decided he wanted to be there at her house in the morning to see what happens. They get in the car, she puts the key in the ignition, pulls out the choke and.......... hangs her handbag on there because that's what it's for.

Remedy, handbag sits on the passenger seat.

19-05-2002, 10:55 PM
Hi Rob if you read this
Very sorry about the posting, But sometimes when you are fixing things like computers sometimes you get bugged by the obvious, Once I was asked to fix TV the customer said was faulty, in workshop good, back in the home faulty, workshop good, home f ........ Ok I am sure you get the picture by now, So Dynamic thinking me put the TV on a Vriac and reduced the mains supply voltage, I only got down to 220 Volts and sure enough, there was the fault just like the customer was complaining about.

20-05-2002, 05:40 PM
No need to apologise to anyone, even if it is a bit off topic. If Robo was around I'm sure he'd enjoy the tale as much as I did.

My hubby is an engineer too, and maintains some highly sophisticated specialised machinery. He has long since learnt that when the machines go down the fault can be caused by something totally unrelated to what the symptoms display. An open mind and lots of imagination is essential in his job.