The Sierra Club hopes to embarrass Ford Motor Co. with ads slated to run in the New York Times and BusinessWeek pointing out that the company’s vehicles are less fuel-efficient now than when Ford got its start 100 years ago. The Model T got 25 miles to the gallon; Ford’s fleet now averages 22.6 miles per gallon, and its popular Ford Explorer gets just 16 mpg. Global Exchange and the Rainforest Action Network are also aiming their firepower at Ford, organizing protests around the U.S. to criticize the company for reneging on a pledge to boost the fuel economy of its SUVs 25 percent by 2005. The first in a series of planned demonstrations took place in San Francisco over the weekend, and as many as 20 cities, including New York and Chicago, will see protests next weekend. All the action will culminate at Ford’s headquarters in Dearborn, Mich., on June 14-16, when the company will be celebrating its 100th anniversary.