“Problems are rolling all around in front of your eyes,” Mr. Toyoda said of those days in “Inside the Mind of Toyota.” “Whether you pick them up and treat them as problems is a matter of habit. If you have the habit, then you can do whatever you have a mind to.”

In 1950, he set out on what would turn out to be a pivotal three-month tour to survey Ford’s Rouge plant in Detroit, then the largest and most efficient factory in the world. Before World War II, the military government prevented Toyota from building passenger cars, compelling it to make trucks for Japan’s war effort instead.

By 1950, Toyota had produced just 2,685 automobiles, compared with the 7,000 vehicles the Rouge plant was rolling out in a single day, according to “The Machine That Changed the World,” a 1990 study by James P. Womack, Daniel T. Jones and Daniel Roos.

Mr. Toyoda was unfazed, writing back to headquarters that he “thought there were some possibilities to improve the production system.” He brought back a thick booklet that outlined some of Ford’s quality-control methods; the company translated it into Japanese, changing “Ford” to “Toyota” in all references.

Mr. Toyoda went on to oversee Toyota’s Motomachi plant, a huge undertaking that gave the automaker the capacity to produce 5,000 passenger vehicles a month at a time when all of Japan produced about 7,000 vehicles a month. The plant, completed in 1959, was soon running at full capacity and gave Toyota a decisive lead over its domestic rival Nissan and the confidence to turn its eyes overseas.

Even as he aggressively expanded production at Toyota, Mr. Toyoda applied a manufacturing culture based on concepts like “kaizen,” a commitment to continuous improvements suggested by the workers themselves, and just-in-time production, a tireless effort to eliminate waste. Those ideas became a core part of what came to be called the Toyota Production System and a corporate ethos known as the Toyota Way.

“One of the features of the Japanese workers is that they use their brains as well as their hands,” he said in an interview with the author Masaaki Imai for the 1986 book “Kaizen.” “Our workers provide 1.5 million suggestions a year, and 95 percent of them are put to practical use. There is an almost tangible concern for improvement in the air at Toyota.”