Comparison of performance using wide-band versus narrow-band oxygen sensors in gasoline engines

Abstract

Spark ignition engines are the most widespread in the automotive industry, they consume more than 35% of the liquid fuel. Therefore, it is of a great value to reduce this percentage the minimum possible. Using electronics and direct injection with the wide-band oxygen sensor may be the technology to solve this problem since traditional electronic control systems use reference stoichiometry to regulate air fuel ratios, using the wide-band oxygen sensor permits the use of reference air fuel ratio values over a wider range.Experiments were carried out on a 4-cylinder 1.8 L displacement volume Mitsubishi 4G93 DOHC GDI using the narrow-band lambda oxygen sensor and the wide-band lambda oxygen sensor, utilizing a lean air-fuel ratio. Road load test conditions were considered. A dynamometer was used in addition to a scan tool and an exhaust gas analyzer. Development extensive work was carried out to correct the single-band to wide-band.The obtained results show that using the wide-band oxygen sensor improves brake specific fuel consumption by 8.8–11.6% between 25% and 100% throttle openings. Whereas, HC and NOx emission gases were reduced by 19.4% and 27.3%, respectively. Keywords: Narrow-band and wide-band oxygen sensors, Air fuel ratio, Gasoline direct injection engine, Lean SI engines operation, Closed-loop lambda control