Oil could also be a factor Wednesday. After rallying Tuesday on Kuwait's oil worker strike, West Texas Intermediate futures slipped late in the day on the announcement of a surprise build in the latest American Petroleum Institute report. It fell further after reports that the strike was settled.
U.S. inventory data is reported at 10:30 a.m. EDT Wednesday, and the May WTI futures contract expires at the close. The May contract ended the day at $41.08 per barrel.
Illinois Tool Works, a closely watched industrial, and Coca-Cola, a multinational consumer bellwether, both report before the bell Wednesday morning. Abbott Labs, St. Jude Medical, U.S. Bancorp, Canadian Pacific Railway and EMC also report before the market open, while American Express, Qualcomm, F5 Networks, Mattel, Yum Brands and Stryker report after the close.
Some earnings so far have been big disappointments. Netflix tumbled nearly 13 percent on its subscriber guidance, while IBM fell more than 5 percent Tuesday after reporting disappointing revenues and guidance Monday.