(Close): US shares closed lower - depressed by weak reports on the US and Chinese economies.
Activity at US factories remained at a two-year low in September. In China manufacturing activity contracted to a six-and-a-half year low.
Suppliers to Volkswagen continued to be hit after the world's largest carmaker admitted to deceiving US regulators over emissions tests.
Shares in Delphi Automotive fell 0.5% and Honeywell lost 1.5%.
On the Nasdaq Clean Diesel Technologies opened up 10.6%, but later fell back to close 4% higher.
The Dow Jones fell 0.3% to 16,279, the S&P 500 lost 0.2% to close at 1,938 and the Nasdaq Composite closed a fraction lower at 4,752.
"The market looks tired and flat, and there is some hesitation to commit with earnings coming out in two weeks and worries about China and the impact on companies that do a lot of business overseas," said Daniel Morgan, senior portfolio manager at Synovus Trust Company.
