Minutes from the meeting showed almost all the policymakers on the central bank's Federal Open Market Committee agreed that a change to the stimulus was not yet appropriate, and only a few thought it would soon be time to "slow somewhat" the pace of the stimulus policy.
"The minutes didn't tell us much. It tells us that like everybody else the Fed is confused and they are not getting any clear signals from the economy. That is what you see in an economy bumbling along at 2 percent," said Erik Davidson, deputy chief investment officer for Wells Fargo Private Bank in San Francisco.
The release of the minutes in midafternoon sparked volatility in equity markets, as the major indexes fluctuated between session lows and highs in the final hours of trading.
The volatility was exacerbated by light volume, with about 5.58 billion shares traded on the New York Stock Exchange, NYSE MKT and Nasdaq, below the daily average of 6.31 billion.
Yields on the 10-year U.S. Treasuries note rose after the announcement, touching 2.89 percent. (US/)
Market participants have been cautious recently, with the S&P 500 dropping for five of the past six sessions amid uncertainty over how soon the Fed will begin to wind down its $85 billion a month stimulus program.
"It's only a question of how much they are going to let up on the gas. There is no question they will not be tapping on the brakes," said Davidson.
Some Fed officials have said the policy, which has fueled Wall Street's steep gains this year, could be slowed as early as September, assuming economic growth meets its targets.
Economic data earlier on Wednesday showed U.S. home resales rose in July to their highest level in over three years, suggesting that a surge in mortgage rates is having only a limited impact on the housing market recovery.
The Dow Jones industrial average (^DJI) fell 105.52 points or 0.7 percent, to 14,897.47, the S&P 500 (^GSPC) lost 9.53 points or 0.58 percent, to 1,642.82 and the Nasdaq Composite (^IXIC) dropped 13.801 points or 0.38 percent, to 3,599.79.
The Dow has fallen for six straight sessions, matching the longest losing streak since July 2012.