Inside Line: Honda Plans Diesel Engine and 65-mpg Hybrid for U.S. - Inside Line: Honda Plans Diesel Engine and 65-mpg Hybrid for U.S. -: "Honda is working on so-called homogeneous-charge compression-ignition or HCCI engines. These power plants ignite the air-gasoline mixture by compressing it, as a diesel does, rather than using a spark plug — but at lower temperatures. The company says it expects to show a prototype four-cylinder HCCI system as early as next year."  ¶ Posted By james 6:14 PM