* Major indexes still poised to tally positive week
* Twitter jumps on reports company exploring sale
* Indexes down: Dow 0.58 pct, S&P 0.47 pct, Nasdaq 0.5 pct (Updates to late afternoon)
By Lewis Krauskopf
Sept 23 (Reuters) - Wall Street pulled back on Friday as lower oil prices weighed on energy shares and tech giants Facebook and Apple declined, although major indexes were still on pace to end the week higher.
Energy was the worst-performing major S&P sector, dropping 1.4 percent. Oil prices tumbled about 4 percent on signs Saudi Arabia and Iran were making little progress in achieving agreement ahead of talks by crude exporters aimed at freezing production.
Facebook shares fell 1.7 percent and were one of the biggest drags on the S&P. The Wall Street Journal reported that the social media company overestimated viewing time for video ads.
Even so, the S&P 500 was set for its best weekly performance in more than two months. Stocks were given a boost on Wednesday when the U.S. Federal Reserve decided to keep interest rates steady, leaving intact the low rate environment that has helped fuel the bull market.
"I just think after a few strong days and a little weakness in energy that folks are taking some profit before the weekend...," said Gary Bradshaw, portfolio manager with Hodges Capital Management in Dallas. "I just feel like the market is going to keep grinding higher."
The Dow Jones industrial average fell 105.88 points, or 0.58 percent, to 18,286.58, the S&P 500 lost 10.16 points, or 0.47 percent, to 2,167.02 and the Nasdaq Composite dropped 26.62 points, or 0.5 percent, to 5,312.90.
For the year, the benchmark S&P 500 is up 6 percent. With the highly anticipated Fed decision now past, investors are turning toward the upcoming corporate earnings season and U.S. presidential election, with the first debate on Monday.
"The market is taking a bit of a breather after a strong week," said Mike Bailey, director of research at FBB Capital Partner, in Bethesda, Maryland.
"Investors are saying markets are already expensive and they've become more expensive this week, so this is a bit of a reversal."
Eight of 11 major S&P sectors were lower. The tech sector fell 0.9 percent, with Apple shares down 1.5 percent.
Twitter shares surged 20 percent amid reports that the microblogging company was exploring selling itself.
Endo International shares jumped 15 percent, the biggest percentage gainer on the S&P, after the drugmaker announced a new chief executive.
Declining issues outnumbered advancing ones on the NYSE by a 1.98-to-1 ratio; on Nasdaq, a 1.45-to-1 ratio favored decliners.
The S&P 500 posted 7 new 52-week highs and no new lows; the Nasdaq Composite recorded 77 new highs and 11 new lows. (Additional reporting by Tanya Agrawal in Bengaluru; Editing by Don Sebastian and Dan Grebler)