Abstract
The LPG vehicles are being operated by commercial purposes generally such as taxis. Most of taxis have a long-mileage and a harsh driving pattern. These properties may accelerate aging of the three-way catalysts much faster than the passenger vehicles. Because of this background, it was analyzed the test result of fuel efficiency and emissions on the LPG-fueled light duty vehicle. It was selected for a LPG vehicle of ULEV level to measure the fuel efficiency and emissions of the aged three-way catalysts. And the aged three-way catalysts which was driven about 300,000km and 550,000km replaced on the test vehicle in consecutive order. As a result, The aged three-way catalysts generally had no effect on fuel efficiency result, and harmful exhaust emissions had been shown to increase in most of the test mode, even though it satisfied the regulation value on most test modes.