The Sensex closed 164 points down at 16617. It had gained 59 points, to 16,841, in opening trade, this morning, on renewed buying by funds at lower levels. Remaining firm, the Sensex went up by 76 points in the noon trade, but closed in the red.Other Asian bourses in Japan, South Korea, Singapore, Indonesia and Hong Kong all posted modest gains, today, after US central bank chairman Ben Bernanke said US economic recovery is intact.