The Dow Jones Industrials came out of their morning funk, but remained lower 25.4 points to break for lunch at 32,627.80.
The S&P 500 sagged 17.31 points to 3,838.79.
The NASDAQ dropped 103.75 points to 10,787.09, dragged down by popular technology stocks.
The Fed is widely expected to announce a 0.75-percentage-point rate increase, its fourth hike in a row of that caliber, as it battles high inflation. Investors are also looking for a signal that the central bank is prepared to slow the pace of its rate-hiking plan come December.
Comments from the Fed and Chair Jerome Powell will play a key role in deciphering where stocks go in the months ahead and whether markets kick off a fresh bull run.
Earnings season continued with strong results from CVS Health. Advanced Micro Devices rose despite a top and bottom line miss.
Shares of Boeing jumped as much as 5.5% as Wall Street cheered comments made at the company’s investor day about full-year positive cash flow.
Treasury prices drooped, raising yields back to Tuesday’s 4.05%. Treasury prices and yields move in opposite directions.
Oil prices heightened $1.74 to $90.11 U.S. a barrel.
Gold prices fell 30 cents to $1,649.40 U.S. an ounce.