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In order to clarify future automobile technologies and fuel qualities to improve air quality, second phase of Japan Clean Air Program (JCAPII) had been conducted from 2002 to 2007. Predicting improvement in air quality that might be attained by introducing new emission control technologies and determining fuel qualities required for the technologies is one of the main issues of this program. Unregulated material WG of JCAPII had studied unregulated emissions from gasoline and diesel engines. Eight gaseous hydrocarbons (HC), four Aldehydes and three polycyclic aromatic hydrocarbons (PAHs) were evaluated as unregulated emissions. Specifically, emissions of the following components were measured: 1,3-Butadiene, Benzene, Toluene, Xylene, Ethylbenzene, 1,3,5-Trimethyl-benzene, n-Hexane, Styrene as gaseous HCs, Formaldehyde, Acetaldehyde, Acrolein, Benzaldehyde as Aldehydes, and Benzo(a)pyrene, Benzo(b)fluoranthene, Benzo(k)fluoranthene as PAHs.

In recent years, designers have attributed increasing importance to reducing noise in car interiors, and various improvements have led to a steady decrease each year in said interior noise. More recently, there has been abundant research on quantitative and qualitative approaches to interior noise, including studies on improving sound quality, such as elimination of rumbling noise and creating a feeling of linearity. Particularly engine noise, one of the major causes of interior noise, has been studied from various angles and significantly reduced in recent years. This has led in turn to increased interest in air induction noise which was a relatively minor noise source in the past. One method of reducing induction noise is the addition of several resonators to the induction system. Induction system components, including resonators, have a major effect on engine output and fuel consumption.

A closed loop lean limit control system by using engine roughness was studied. This system controls the air-fuel mixture close to optimum for fuel economy, which is a little richer mixture than lean misfire limit by measuring engine roughness using the information from engine speed signal. A magneto resistance type engine speed sensor was utilized as a roughness sensor and the engine roughness was calculated from that signal by a 12 bit micro-computer. It was found that the engine roughness correlated well with the variation of combustion on the dynamometer test. Some correlation measures to eliminate irregular fluctuations caused by load variations on the rough road driving condition or engine torque variations on the acceleration and deceleration condition of a vehicle, were applied to the micro-computer program. It was confirmed that the closed loop lean limit control system functioned satisfactorily. About 7% higher fuel economy than conventional system was obtained.

The development of new systems to reduce exhaust gases is being investigated in response to OBD-II regulations and regulations all over the world relating to the introduction of low exhaust gas vehicles (LEV, ULEV, STEP3, STEP4). We have developed a highly responsive thermistor type catalyst temperature sensor that is very accurate, highly heat resistant, has a wide detection range, and that can be used in exhaust gas cleansing systems. The key technologies used in this new catalyst temperature sensor are: 1 Wide detection range: The thermistor is of a network construction that comprises a semi-conductor with a new Y-Cr-Mn perovskite crystal structure and an insulator. The temperature range can be set by changing the proportions of semi-conductor and insulator.

Toyota Motor Corporation (TMC) has been developing fuel cell (FC) technology since 1992, and finally “MIRAI” was launched in 15th Dec. 2014. An important step was achieved with the release of the “FCHV-adv” in 2008. It established major improvements in efficiency, driving range, durability, and cold start capability. However, enhancing performance and further reductions in size and cost are required to facilitate the commercial widespread adoption of fuel cell vehicles (FCVs). TMC met these challenges by developing the world's first FC stack without a humidifying system. This was achieved by the development of an innovative cell flow field structure and membrane electrode assembly (MEA), enabling a compact and high-performance FC stack. Other cost reduction measures incorporated by the FC stack include reducing the amount of platinum in the catalyst by two-thirds and adopting a carbon nano-coating for the separator surface treatment.

In the case of two-stroke cycle gasoline engines, it is a rather well known fact that under light-load operation they do not run smoothly, but have a high concentration of unburned hydrocarbons (HC) in the exhaust gas, as well as high a fuel consumption rate. In the study to improve such unstable conditions by devising a scavenging process of the engine, we often encountered self-ignited combustion, a kind of “RUN-ON”. This combustion was found to be very stable and fine with low missions of HC, and improved fuel consumption. A study was carried out on this self-ignited combustion by optical analysis. Many differences were observed between self-ignited combustion and conventional spark ignited combustion on the behavior of formation of chemical intermediate products before and after ignition. Self-ignited combustion has been found to occur under relatively low cylinder pressure and temperature, compared to diesel engine combustion, presumably by virtue of intermediate products.