U.S. consumer prices rose marginally in September from August, restrained by weak food and housing costs, according to government data on Thursday that pointed to scant inflation pressures as the economy makes a comeback from recession.

The Labor Department said its Consumer Price Index rose 0.2 percent last month, matching analysts' expectations, after increasing 0.4 percent in August.

Consumer prices are being closely watched for signs of inflation pressures in the wake of massive efforts by the government and the Federal Reserve to stimulate the economy out of a recession that started at the end of 2007.

Economic growth is believed to have resumed in the third quarter, but labor market slack will probably keep price pressures muted for a while and keep deflation on the radar.

The small monthly increase in September came as the food index dipped 0.1 percent, falling for the sixth time in the last eight months.

Compared to the same period last year, consumer prices dropped 1.3 percent, with the food index declining from a year earlier for the first time in 40 years. Consumer prices have been falling on an annual basis since March.

Stripping out volatile energy and food prices, the closely watched core measure of consumer inflation inched up 0.2 percent from August, a touch above market expectations for a 0.1 percent gain.

Core prices were lifted by a bounce in new vehicle prices following the expiry of the popular cash for clunkers program that gave discounts to consumers to trade in their old gas-guzzling cars for new, fuel-efficient ones. New vehicles rose 0.4 percent after plummeting 1.3 percent in August.

The increase in core inflation came despite rentals and owners equivalent rent indexes posting their first declines since 1992.

Compared to August last year, the core inflation rate rose 1.5 percent after increasing 1.4 percent in August.

(Reporting by Lucia Mutikani; Editing by Neil Stempleman)