The Sensex opened with a positive gap of 14 points 13,963. The index touched a high of 13,989, and then slipped into the negative zone to a low of 13,920.The index has now rebounded into the positive zone and is now up eight points at 13,957.HDFC has dropped nearly 2% to Rs 1,560. ONGC is down nearly 1% at Rs 858.Maruti, Reliance and HDFC Bank are the only notable gainers.