Japanese investors got a scare on Thursday when the Nikkei (NIKKEIINDICES:^NI225) took an unexpected dive after last Thursday's 7% single-day loss. The index managed to pull back some of its gains on Friday, but it still shed more than 3% for the week. Despite the negativity from investors, Japan got a big boost to end the week from data that showed that Prime Minister Shinzo Abe's aggressive stimulus plan is working. If it keeps up, this week's losses could be just the right dip for investors to capitalize on a new growth spurt across the Pacific.

Abe-nomics hits the right marks
The Tokyo metropolitan area's core consumer price index, a measurement that's often taken as a reading on Japan's greater inflation as a whole, grew by 0.2% in April and 0.1% year over year -- its first growth in four years. Japan's overall core CPI fell 0.4% year over year, but the country's deflation has been declining over the past few months as the impact of Abe's easy money spreads.

Japan's a long way away from hitting Abe's 2% inflationary target, but slowing deflation and the yen's dramatic fall against the dollar over the course of 2013 are great starts. Indeed, it's already helped industrial companies move forward, as Japan's industrial production advanced 1.9% for the month. Japan will still have to deal with its world-leading public debt problem, but the third-leading economy's move toward growth is something that investors and companies alike should celebrate.

What's in it for the automakers?
It could be a big trend for automakers such as Toyota (NYSE:TM) that rely heavily on exports. A cheap yen will make overseas investment more expensive for Toyota and its peers, but international sales will mean more for its revenue as Japan's currency falls. The world's leading automaker has predicted that U.S. sales will grow in May, particularly as its Prius hybrid model gains traction in the market.

The Prius has underperformed significantly so far in 2013, and Toyota's still facing tough competition. Leading rival General Motors (NYSE:GM) is the top automaker in China's surging auto market even as Toyota surpassed the firm as the largest car company in the world. Toyota will have to keep pressing in the U.S. to keep up with its rival, as GM posted its best April sales growth in five years this year, growing the figure by 11% for the month alone.

Competing Japanese automaker Honda (NYSE:HMC) isn't quite on GM's and Toyota's level, but the company's going after the latter's Camry hybrid sedan for Japanese sales. Honda's now preparing to sell a new hybrid version of the Accord slated to boast the highest fuel economy in its class, offering nearly seven kilometers per liter more fuel efficiency than the Camry hybrid. The Accord's performed exceptionally in the U.S., ranking as the nation's top-selling car in April and growing sales by 26% this year alone. Honda's overall sales are still lagging Toyota, but this firm's winning in U.S. sales growth in the midsize category.

Automakers across Japan are thriving this year, and even Nissan (NASDAQOTH:NSANY) is joining the party. The company's sales hit an all-time record in April by growing 0.2%, although Nissan's sales have lagged in Japan and fell off by 4.8% year over year for the month. As with Honda, Nissan's sales of vehicles have surged in the U.S.

With the average car on American roads aging and consumer confidence hitting highs, Americans are set to continue the auto industry's good year throughout 2013. As the yen falls further, those U.S. sales will mean all the more to Japanese automakers and their shareholders.

Fool contributor Dan Carroll has no position in any stocks mentioned. The Motley Fool recommends General Motors. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.