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Concerns such as depletion of petroleum fuels and global warming are placing more severe demands on internal combustion engines each year for reduced fuel consumption and CO₂ emissions. Countries around the world have set regulations that drastically reduce CO₂ emissions from vehicle exhaust. In order to meet these requirements, various new engine technologies are being developed. One of the technologies to cut CO₂ emissions of the SI engine is the combination of reduced displacement, high compression ratio, forced induction, and direct fuel injection. But in this downsized engine, abnormal combustion, which occurs under the condition of low speed and high intake pressure, is a serious problem. It has been referred to as Super Knock, Mega Knock or Low Speed Pre-Ignition (LSPI). In this paper, we use the term Super Knock. Many research institutions and car manufactures have been investigating this abnormal combustion, but the exact cause is still unknown.

Anti-shudder characteristics are an important part of automatic transmission fluid (ATF) performance. Anti-shudder performance has two aspects, initial friction aimed at the prevention of “green shudder” and anti-shudder durability which is the prevention of shudder at high vehicle mileage. Different methods of measuring anti-shudder durability give different results. We have found that some fluids give very acceptable performance when measured in a Low Velocity Friction Apparatus (LVFA) test, such as a JASO M349-2001 [1] , do not give good results when measured in a method that includes high energy engagements and oxidation. This apparent anomaly in test results is due to unexpected behavior of certain fluids after oxidation. The observation is a cause for concern relative to the widely accepted JASO method.

The design of spark plugs, critical for igniting the gas mixture in the combustion chamber, must catch up with the latest advances in automotive engine development because many improvements for higher efficiency and lower emissions make combustion more difficult to initiate. Spark plugs must maintain their function in both below freezing environments and high speed, high temperature operation. The performance of a spark plug is characterized by the shape of its firing end exposed in the combustion chamber and the layout of the insulator nose in the metal shell. This paper summarizes recent requirements for spark plugs, proposes a new firing end shape, and evaluates its performance. The relationship between geometric configuration and performance are evaluated on an actual engine. The results demonstrate improved spark plug performance, especially under the most extreme temperature conditions.

The direct injection (DI) gasoline engine has drawn considerable attention recently for energy savings and emission reductions. Compared with current port fuel injection (PFI) engines, DI engines are designed to have high specific power output, low fuel consumption and low emissions at the same time. Among others a feature of the DI gasoline engine is its capability to freely alter the state of combustion from homogeneous to stratified combustion at different load conditions. Engines with high power density such as the DI engine, are also prone to knock. To suppress engine knocking a flexible and precise combustion control mechanism is required. The paper being presented describes some of the characteristics required for spark plugs utilized in DI gasoline engines.

In the past few years, car navigation and cellular phone system are rapidly increased in Japan and vehicle information and communication system (VICS), the public traffic information service started in 1996, accelerates realization of ITS world. This rapid movement causes drivers to want more information on not only traffic jam but also other versatile items like parking availability, weather report and the latest news, etc. via cellular phone network. This paper describes the on-demand information service with the interactive human interface by operators and the development of the information center and the in-vehicle system to realize it.

A prototype navigation system with cellular phone access to an information service center was constructed and evaluated. Center personnel can also operate the system remotely, in addition to providing traffic information and information for more enjoyable travel. Real-time conversation with a center operator is also possible. The system was rated positively by most of the subjects, especially the real-time voice service. This paper describes the car navigation market and cellular phone market in Japan, the system configuration, evaluation results and possible solutions to problems in the system. It also touches on the outlook for future car navigation systems and information services.

ASICs (Application-specific ICs) offer one solution to the problems of quality, cost and installability associated with the increasingly larger-capacity Electronic Control Units (ECUs) in automobiles. A method was, therefore, created for designing automotive ASICs. Using the method, three ASICs were developed which, together, incorporate all of the functions of the electronic instrument cluster. The core ASIC contains the speedometer and system functions, and the other two ASICs contain the tachometer and gauge functions, respectively. This set of three ASICs allows an electronic instrument cluster design which is two times more reliable, and one-second the cost that conventional systems (with a micro-processor and discrete components).