$1B Cash for Clunkers program out of money

Dealers sold nearly 250K vehicles since program started in early July

Program designed to revive slumping auto sales, remove gas guzzlers

Program was to be suspended but White House sought new money

About 16K dealers were eligible for program

NADA says each would have to sell 12 vehicles to reach funding limit

Some lawmakers want more fuel efficiency requirements before approving more money

Not clear how program has affected automakers that sell fuel-efficient cars

"We hope there's a will and a way to keep the program going a bit longer. Any doubt that the program would jump-start auto sales is completely erased." -- statement, General Motors