Stocks: Signs of Spring?

NEW YORK (CNNMoney)

U.S. stock futures were all trading firmer Tuesday, and most global indexes were firmly in the green.

Investors will be looking to the ISM manufacturing index -- due out at 10 a.m. ET -- for the latest clues on the health of the U.S. economy, after Janet Yellen said Monday that the Federal Reserve's repair job was not yet finished.

General Motors (GM, Fortune 500) will also take center stage. Its shares continued to slide in extended trading Monday after the company announced another recall and set aside more money to cover the costs.

GM has been criticized for how it handled a different recall due to faulty ignition switches, linked to the deaths of 13 people. CEO Mary Barra will testify before Congress on Tuesday and Wednesday about the problems.

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U.S. stocks ended higher Monday. The Dow rose about 135 points, while the S&P 500 is at 1872, within spitting distance of its all-time high (1883, set earlier this month). The Nasdaq jumped over 1%.

But shares of Caterpillar (CAT, Fortune 500) fell after a report claimed it avoided $2.4 billion in taxes.

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European markets were broadly firmer in morning trading, while Asian markets ended mixed. Tokyo's Nikkei dipped 0.2% on the first day of a sales tax hike that will bring the rate to 8% from 5%, a new potential drag on the economy.

China markets ended in positive territory despite the release of muddled data on the country's factories. The Hang Seng added 1.3% and the Shanghai Composite rose 0.7%.