DETROIT - Buick will offer its LaCrosse CX model with a new fuel-efficient, direct-injected Ecotec 2.4L four-cylinder engine in 2010, according to the automaker. The four-cylinder is the third engine choice in the all-new 2010 Buick LaCrosse luxury sedan. Backed by a six-speed automatic transmission, the new powertrain combination is expected to deliver fuel economy of 30 mpg highway and an estimated 20 mpg cityking.

 The Ecotec 2.4L four-cylinder joins the lineup in the first quarter of 2010 as the standard engine in the LaCrosse CX. Direct injection technology helps it deliver 182 horsepower and 172 ft.-lb of torque.

The 2.4L's injection of fuel directly into the combustion chamber enables a higher compression ratio to increase efficiency and horsepower, reducing cold-start emissions by up to 25 percent, according to Buick.