The Sensex opened on a flat note at 8,499, but soon plunged to a low of 8,262 - a drop of 238 points from yesterday's close of 8,500.The index bounced back in late noon deals to touch a high of 8,521 - an intra-day swing of 259 points. The Sensex finally finished with a loss of 13 points at 8,487.HLL was down 2.4% (Rs 4) at Rs 171. ONGC added Rs 9 at Rs 1,039. While Reliance was up Rs 4 at Rs 783, SBI gained Rs 2 to Rs 919. ITC was up at Rs 140.Infosys declined 1.3% (Rs 32) to Rs 2,465. TCS dropped Rs 17 to Rs 1,453.Grasim slipped Rs 18 to Rs 1,361. ACC and Gujarat Ambuja also declined.HDFC was down 4% (Rs 39) at Rs 990.Bajaj was up Rs 8 at Rs 1,664, and Hero Honda moved up Rs 5 to Rs 708.NTPC zoomed over 4% (Rs 5) to Rs 108. BHEL was up Rs 7 at Rs 1,135.