Sensex is 159 points up at 17,224 in afternoon trade. Sensex, which gained 173 points in the previous trading session, added another 149 points to touch 17,213 in the first five minutes of trading today. The broad-based National Stock Exchange Nifty gained42.55 points to 5,161.90. The good start in the market was amplified by an upsurge in the Asian stock market.