Stocks plummeted from modest losses into the red before charging higher again in the final two hours of trading on Wednesday. Market activity was erratic after the Federal Reserve kept rates unchanged, but left a potential December hike on the table. There was more excitement over on the commodity markets after crude oil enjoyed its best day in three months. A 5% jump in oil prices boosted the energy sector with major oilers Exxon Mobil (XOM) and Chevron (CVX) among the best performers. The two are due to report earnings on Friday. Boston Scientific (BSX) climbed on a better-than-expected quarter after efforts to diversify from its cardiovascular equipment sales paid off. Overall revenue jumped 9%. The lower end of full-year earnings guidance was also raised.