As Washington fiddles over the debt limit, investors are getting burned in the stock market. The Dow Jones industrial average tumbled Wednesday, dropping 2.2 percent to 12290.14, a drop of 279.65 points. The NASDAQ and S&P also fell about 2 percent. The markets’ bad day was driven by concerns about a disappointing report on housing prices, a downgrade in the Greek government’s credit rating, and a manufacturing slowdown—all leading to a fear that the nascent economic recovery is slowing. Pessimistic expectations for the U.S. monthly job report, to be released Friday, also weighed on the indices. Financial stocks led the charge downward. The one shred of good news? Oil futures declined.