Diesel particulate filters (DPF) require routine cleaning to remove ash that builds up over time. Most vehicles using a DPF system will have an on-board filter service monitor to indicate the filter condition and guide your filter cleaning schedule.
In ancient times the islands formed an independent kingdom. Chinese and Japanese sovereignty were successively forced on the archipelago from the 14th to the 19th century, and in 1879 the Ryukyus became an integral part of Japan. After the defeat of Japan (1945) in World War II, the United States took control of the islands.
Ryukyu Islands (rÄÅÅÂ´kyÅÅ), Jap. Ryukyu-retto or Nansei-shoto [southwest group], archipelago (1990 est. pop. 1,500,000), c.1,850 sq mi (4,790 sq km), SW Japan, in the W Pacific Ocean. The chain stretches about 650 mi (1,050 km) between Taiwan and Japan, separating the East China Sea from the Philippine Sea.