(Updates with fresh details throughout, analyst comment)
* TSX down 48.37 points, or 0.32 percent, at 15,295.71
* Nine of the index's 10 main groups fall
* Energy stocks down 0.7 percent
By Solarina Ho
TORONTO, April 28 (Reuters) - Canada's main stock index fell on Tuesday as investors shied away from making big bets as the U.S. Federal Reserve kicks off its two-day meeting on monetary policy.
A run of lukewarm U.S. economic data during the first quarter has pushed expectations of the Fed raising interest rates until the second half of 2015.
"(The market's) just trying to figure a timing on when we might see an uptick in interest rates," said Brian Pow, vice president of research and equity analyst at Acumen Capital Partners in Calgary.
"I think people are still counting on that liquidity in the marketplace and if that liquidity moves away and the rates go up, then people are going to have a different view of how they look at equities."
The most influential movers on the index included Enbridge Inc, which fell 1.29 percent to C$65.00, and Transcanada Corp, which declined 1.5 percent to C$57.22.
The overall energy group retreated 0.7 percent. The moves contrast with crude prices, which turned positive mid-morning on reports that Iran had seized a U.S. cargo vessel.
Pow noted that crude prices holding near 2015 highs was positive and that the market could see some recovery if prices could hold on to current levels.
At 11:05 a.m. EDT (1505 GMT), the Toronto Stock Exchange's S&P/TSX composite index fell 48.37 points, or 0.32 percent, to 15,295.71.
Of the index's 10 main groups, nine retreated into negative territory.
"We had a pretty run on a lot of names, so I think there's also profit taking - 'sell in May, go away,'" Pow said.
The heavily weighted banks and insurers group fell 0.2 percent.
Royal Bank of Canada fell 0.33 percent to C$80.41:2.
Materials, home to mining companies, were the lone gainers, rising 0.9 percent. It was helped in large part by higher bullion prices, which rose after weak U.S. data hurt the greenback. Gold futures rose 0.2 percent to $1,205.3.
Six of the top eight most influential gainers were gold mining firms. Barrick Gold Corp shares rose 2.6 percent to C$15.92, while Goldcorp Inc rose 2.0 percent to C$23.66. Agnico Eagle Mines Ltd rounded up the top three, advancing 3.9 percent to C$37.84.
Declining issues outnumbered advancing ones on the TSX for a 1.39-to-1 ratio on the downside. (Reporting by Solarina Ho; Editing by Ted Botha)