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How Automotive Fine-Tuning Works

Automotive Fine-Tuning Explained

For companies like Aston Martin and Bentley, fine-tuning expensive, high-performance automobiles is a no-brainer. But why would a mass-market manufacturer, such as Toyota or Nissan, go to all the trouble? If one car out of millions made it through with a little rattle, that would be OK, right?

Not at all, according to Barbara McDaniel, manager of external affairs at Toyota. McDaniel says the company's basic philosophy is not to pass a defect along to the customer -- it's part of the design process [source: McDaniel]. Every Toyota auto manufacturing plant has an andon cord at each station on the assembly line. When the person at a station notices a problem, he or she pulls the cord, and a group leader comes to inspect the issue. Typically, the problem can be solved quickly, and the andon cord is pulled again so the manufacturing process can continue. However, if there's a serious problem or defect, the line is stopped until the situation is resolved.

Auto manufacturing is a complicated process, so it's not uncommon for problems to occur on occasion. For example, in 2003, Nissan began finding flaws in some of the vehicles produced at its Canton, Miss., plant and had to locate the source of the problem. Fuel doors weren't fitting correctly on some cars, and it was soon discovered that an unreliable gauge was being used to measure the part. Nissan also realized that the lighting in its inspection area was too dim to identify some minor problems during a vehicle's examination [source: Zachary].

Nissan, of course, fixed the issues at its Mississippi plant, and the company continues to improve its fine-tuning process. In fact, all auto-manufacturing plants are constantly looking for ways to improve their fine-tuning methods. Keep reading to learn what improvements have occurred in recent years.