Nissan Motor Co. will soon sell cars with accelerators that push back when drivers try to put the pedal to the metal. It has also developed a test model packed with added sensor technology to avoid collisions.

The features unveiled this week by Nissan Motor Co. are the latest among recent efforts by the world's automakers to vamp up their images.

Nissan's collision-free prototype has sensors at its back and side that turn on alarms and brakes to help avoid collisions. The system also helps the vehicle maintain a safe distance with the car in front, as well as preventing it from veering out of its lane, Nissan said Tuesday.

Nissan has said it hopes to halve the number of traffic accidents or serious injuries involving its vehicles in Japan by 2015 compared with 1995 levels.

Nissan's ECO Pedal system — promoted as being both green and safe — makes the gas pedal press upward when it senses motorists are speeding up too quickly.

Nissan said in a press release the system, which will be available next year, can help drivers improve fuel efficiency by 5 percent to 10 percent.

The system calculates the most efficient rate of acceleration in a vehicle based on how fast fuel is being burned and other factors and causes the gas pedal to push back to alert overzealous drivers. A special meter on the dashboard flashes and changes colors to help drive the message home.

Nissan said the system is designed to help drivers become more fuel efficient behind the wheel. Part of the company's strategy for reducing carbon dioxide emissions is modifying driving behavior.

Drivers can also opt to switch the system off.

Soaring gas prices and worries about climate change are pressuring automakers to introduce ecological products.