DETROIT -- General Motors says it is working on the next generation of its gas-electric mild hybrid system that will be more efficient than the one it is canceling in the Chevrolet Malibu and Saturn Aura.
Company spokesman Terry Rhadigan says cars equipped with the current system weren't selling and inventory is backing up on dealer lots.
Rhadigan says the new system will debut with new models in the summer of 2010. He would not identify which vehicles will get the new system.
The current system costs almost $4,000 more than the conventional base model Malibu but gets only four miles more per gallon of gasoline.
The hybrid system cuts off the engine when the car stops and uses an electric motor to help the gasoline engine get the car going again.