The NGK AFX is a true air/fuel monitor that senses exhaust oxygen, carbon monoxide, hydrogen, and hydrocarbons in the exhaust and calculates real time air fuel ratio (AFR). Air Fuel Ratio is a crucial parameter that dictates horsepower and engine performance. Performance enthusiasts and tuners can use Air Fuel Ratio information to make adjustments to the fuel delivery system (carburetor, fuel injection) to help achieve the maximum horsepower available from their engine. The AFX is compatible with both Bosch LSU and NTK UEGO (wideband) sensors without any changes in hardware or programming and offers superb accuracy (comparable to some laboratory grade systems).

The NGK AFX Air Fuel Ratio Monitor is the most affordable "true" wideband technology to date. Many low-cost air-fuel ratio monitors do not use wideband sensors; they simply manipulate a standard narrow-band oxygen sensor signal with rough inaccurate data resulting in only marginal success.

Traditionally these types of tools commanded price tags in the thousands of dollars putting them out of reach for most enthusiasts and amateur/grassroots racers. NGK's advances in technology have made this highly accurate tool affordable.

The NGK AFX has a 0 ~ 5V, linear analog output for AFR that can be used as an input to an engine controller, data acquisition system, or analog gauge with 0 to 5 volt input.