At close, the BSE Sensex was down 1.86 points, or 0.01 per cent, at 32,400.51. Nifty50 fell 6.40 points, or 0.06 per cent, to settle at 10,141.15. Fear gauge India VIX, which suggests volatility in the market over next 30 days, rose 1.46 per cent to 11.63.Watch: Sensex, Nifty end flat in cautious trade ahead of Fed outcome