WASHINGTON, March 16 (Reuters) - U.S. factory production increased marginally in February as strength in motor vehicle output was offset by weakness in machinery, data showed on Monday.

Manufacturing output rose 0.2% last month after an upwardly revised 0.8% gain in January, the Federal Reserve said.

Economists polled by Reuters had forecast production for the sector, which accounts for 10.1% of the economy, rising 0.1% after a previously reported 0.6% rise in January. Production at factories advanced 1.3% year-on-year in February.