A coalition of enviro and consumer groups is calling for an end to one of Al Gore’s pet projects, the Partnership for a New Generation of Vehicles, under which the federal government and Big Three U.S. automakers have teamed up to develop highly fuel-efficient cars and trucks. Critics point out that despite the millions of dollars the government has put into the project, U.S. automakers have yet to market cleaner vehicles. Enviros also criticize the project for focusing on diesel models, which they say produce too much pollution, and they contend that automakers are using their participation in the voluntary program to argue against raising fuel-efficiency standards. Last week, enviros helped persuade the House to cut the program’s proposed $255 million budget by about 50 percent. Meanwhile, Gore yesterday proposed giving Americans tax credits for buying energy-efficient cars and houses.