Stock index futures were lower on Wednesday following a sharp rally in the previous session as the market displayed little trend except volatility ahead of the upcoming Federal Reserve meeting.

Hopes that Fed Chairman Ben Bernanke would announce new stimulus for a struggling U.S. economy fueled Tuesday's 3 percent rally.

A Washington Post article grabbed market attention overnight, playing down the likelihood Bernanke would announce big plans to boost the economy in a speech on Friday.

The Washington Post story is why the S&P is giving back some of its gains, said John Brady, senior vice president at MF Global in Chicago. The movement in risk assets suggests disappointment over the idea that there will be no new policies, and that should hinder domestic bank performance.

Bernanke will speaks at a central bank conference in Jackson Hole, Wyoming that starts Thursday. Analysts are divided on how much room the Fed has for further stimulus.

Bank of America Corp fell 1.6 percent to $6.20 in premarket trading, extending losses from the previous day, when the Dow component fell at one point to 2-1/2-year lows on fears it may have to raise massive amounts of capital.

Concerns about the economy's strength and the euro zone's sovereign debt crisis have sparked sharp volatility in the past two weeks, and the magnitude of Tuesday's rally echoed the steep moves.

S&P 500 futures fell 8.7 points and were below fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures lost 70 points, and Nasdaq 100 futures sank 12 points.

Investors looked ahead to July data on durable goods, seen up 2 percent on orders for cars and planes, reversing a weak June, when orders fell by 1.9 percent. The data is due at 8:30 a.m. EDT.

MF Global's Brady said the data was unlikely to move markets unless it was weaker than expected, as the airplane orders were seen giving a strong headline number.

In earnings news, Toll Brothers Inc reported third-quarter revenue that missed expectations and narrowed its home delivery order for the full year.

Applied Materials Inc is scheduled to report quarterly results later Wednesday.

Delta Air Lines Inc is expected to order 100 Boeing Co extended-range 737 planes to replace older aircraft, sources said.

U.S. stocks shot higher Tuesday on hopes for Fed action, giving investors hope that a four-week rout was ending. Technology and other growth stocks drove most of the gains, with the Nasdaq rising more than 4 percent.

(Editing by Jeffrey Benkoe)