Abstract: According to one or more embodiments of the technical solutions described herein, a control system in a motor vehicle that includes an internal combustion engine includes an oxygen sensor, and an oxygen sensor diagnosis module to diagnose the oxygen sensor. The oxygen sensor diagnosis includes performing an intrusive rich-to-lean diagnostic for the oxygen sensor, and detecting a lean-to-rich diagnostic event. In response, the diagnosis includes performing a passive lean-to-rich diagnostic for the oxygen sensor, the lean-to-rich diagnostic event comprising a fuel enrichment.

Abstract: A system for a vehicle includes an oxygen storage capacity (OSC) determination module, a delay determination module, a correction module, and a fault detection module. The OSC determination module determines an OSC period of a catalyst of an exhaust system based on first and second amounts of oxygen measured using first and second oxygen sensors located upstream and downstream of the catalyst, respectively. The delay determination module determines a delay period of the second oxygen sensor. The correction module sets a corrected OSC period for the catalyst based on a difference between the OSC period and the delay period. The fault detection module selectively indicates that a fault is present in the catalyst based on the corrected OSC period.

Abstract: A system for a vehicle includes an oxygen storage capacity (OSC) determination module, a delay determination module, a correction module, and a fault detection module. The OSC determination module determines an OSC period of a catalyst of an exhaust system based on first and second amounts of oxygen measured using first and second oxygen sensors located upstream and downstream of the catalyst, respectively. The delay determination module determines a delay period of the second oxygen sensor. The correction module sets a corrected OSC period for the catalyst based on a difference between the OSC period and the delay period. The fault detection module selectively indicates that a fault is present in the catalyst based on the corrected OSC period.