NGK Spark Plug Co., Ltd. | The American Ceramic Society

NGK Spark Plug Co., Ltd.

30.twinsA_enNGK SPARK PLUG CO., LTD. (hereafter NTK) has been manufacturing oxygen sensors since 1982 and has built on success in the USA domestic market to expand business globally. Recently NTK oxygen sensors have a wide variety of other applications beyond automotive engines.

NTK oxygen sensors are characterized by stable output and excellent durability, features which are essential for the critical role these sensors play in the vehicle emission control system, and which contribute to meeting air quality goals.  NTK is the world’s largest supplier of oxygen sensors for automotive engine combustion control, and continues to be a trusted source for manufacturers globally. In response to ever-tightening emission regulations and the resulting increased demand for precision fuel control, NTK successfully commercialized the wide range oxygen sensor. Moreover, NTK is introducing oxygen sensors with lower electric energy consumption to automotive manufacturers to help them achieve their goals for improved fuel economy.

Now NTK is developing sensing technologies for NOx and particulate matter, which will likely be subject to tighter regulation in the near future. NTK will continue to support the automotive industry by providing advanced technology for tighter emission regulations.

Clean Air Technology

The heart of a zirconia oxygen sensor is the sensing element composed of a zirconia ceramic layer with electrodes attached to both sides. By exposing one electrode to exhaust gas and the other to atmosphere, an electric potential is generated depending on the difference in oxygen concentration. This voltage signal is provided to the engine control module (ECU), which in turn uses this information to control fuel injection such that the air fuel ratio is close to the ideal (stoichiometric) value for optimum efficiency of the catalytic converter. Through this control the oxygen sensor contributes to reductions in harmful pollutants such as NOx, CO and HC.

As the oxygen sensor is installed in the harsh environment of the engine exhaust system, requirements for durability with respect to temperature, vibration, shock and the like are also severe. NTK has drawn on technology developed over many years of spark plug design to overcome the difficult challenges of joining the ceramic sensing element to a robust metal body. The result is a high quality sensor capable of withstanding these severe conditions over the entire vehicle lifetime.

The oxygen sensor is critically important for the vehicle on board diagnostic system (OBD), and it provides a key input for monitoring catalytic converter deterioration and fuel injection system malfunctions. Therefore high reliability is vital. NTK has continued to incorporate advanced ceramics and structural design technology to meet the demands of the market. We believe these superior technologies are essential to customer satisfaction, and have boosted NTK to our current position as the world’s largest producer of oxygen sensors.


NGK SPARK PLUG CO., LTD., headquartered in Nagoya, Japan, is a comprehensive ceramics processing manufacturer. We hold a world leading share of spark plugs and automotive sensors for internal combustion engines and also offer a broad lineup of packages, cutting tools, bio ceramics and industrial ceramics. 

Our global network of sales and manufacturing organizations, and over 14,000 employees deliver value creation to the world. 

We are now contributing to a sustainable society by developing products related to environmental energy, next generation vehicles and medical devices and diagnostics.