The Application of an Air-to-Fuel Ratio Sensor to the Investigation of a Two-Stroke Engine

A rapid response air-to-fuel ratio sensor manufactured by Nissan has been evaluated for use as a diagnostic tool in engine research. The sensor was calibrated for use with methanol and the time response of the sensor was investigated. Using the sensor's capacity as an extended range oxygen sensor, it was used to monitor the exhaust of a methanol fueled, two-stroke research engine fitted with a prototype air-assisted direct-injection fuel injector. Measurements made at various locations in the exhaust line indicated high levels of short circuited intake air and revealed fluctuations in the measurements due to the sensor's sensitivity to temperature and pressure.