* Futures off: Dow 31 pts, S&P 4 pts, Nasdaq 11 pts (Updates prices, adds comment)
By Rodrigo Campos
NEW YORK, Sept 16 (Reuters) - U.S. stocks were set to open lower on Tuesday with traders positioning for a Federal Reserve meeting expected to provide clues on the short term direction of U.S. interest rates.
Futures held on to slight losses after data showed U.S. producer prices were flat in August, pointing to muted inflation pressures that should see the Fed in no hurry to raise rates.
Later on Tuesday, the Fed will begin a two-day policy meeting. A statement and forecasts will be released Wednesday at 2:00 p.m. EDT (1800 GMT) followed by a press conference half an hour later.
"The big news comes (Wednesday) from the Fed and we'll work our way a bit lower before the announcement. Key points will likely suggest the Fed stays on hold until the middle of next year and that is already baked in," said Peter Cardillo, chief market economist at Rockwell Global Capital in New York.
"Markets are in a bit of a technical pullback," he said, adding the benchmark S&P 500 "will test 1,975 and probably could work toward 1,940-1,950, which I think would represent a buying opportunity."
S&P 500 e-mini futures were down 4 points and fair value - a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract - indicated a lower open. Dow Jones industrial average e-mini futures fell 31 points and Nasdaq 100 e-mini futures lost 11 points.
U.S.-traded AstraZeneca shares fell 1.6 percent in premarket trading after it signed a partnership deal with U.S. rival Eli Lilly that could earn the British company up to $500 million if an experimental Alzheimer's drug proves successful.
Editing by Bernadette Baum