Abstract: A diagnostic system for monitoring catalyst performance in an exhaust system comprises a plurality of treatment devices catalytically treating an exhaust gas stream, and a plurality of gas sensors for monitoring the catalyst performance of the treatment devices to determine when sulfur poisoning occurs. An on-board diagnostic system receives signals from the gas sensors, and, based upon response time differentials between sensors, determines whether the treatment devices are experiencing sulfur poisoning.

Abstract: A diagnostic system for monitoring catalyst performance in an exhaust system comprises a plurality of treatment devices catalytically treating an exhaust gas stream, and a plurality of gas sensors for monitoring the catalyst performance of the treatment devices to determine when sulfur poisoning occurs. An on-board diagnostic system receives signals from the gas sensors, and, based upon response time differentials between sensors, determines whether the treatment devices are experiencing sulfur poisoning.

Abstract: A diagnostic system for monitoring catalyst performance in an exhaust system comprises a plurality of treatment devices catalytically treating an exhaust gas stream, and a plurality of gas sensors for monitoring the catalyst performance of the treatment devices to determine when sulfur poisoning occurs. An on-board diagnostic system receives signals from the gas sensors, and, based upon response time differentials between sensors, determines whether the treatment devices are experiencing sulfur poisoning.

Abstract: A catalytic converter for an exhaust system of a motor vehicle comprising a housing having an inlet and an outlet; a first brick positioned inside the housing adjacent the inlet for initiating catalytic light-off functions of exhaust gases flowing through the first brick; a second brick positioned adjacent the first brick downstream of the inlet for three way conversion of exhaust gases flowing through the second brick; a third brick positioned adjacent the second brick downstream of the inlet for hydrocarbon adsorption and oxidation of exhaust gases flowing through the third brick; and a fourth brick positioned adjacent and spaced from the third brick downstream of the inlet for light-off of exhaust gases flowing through the fourth brick; wherein the third brick is substantially annular with a through bore extending axially therethrough; and wherein the second brick has a closed bore extending axially and opening into the through bore of the third brick.

Abstract: A catalytic converter (10) for an exhaust system of a motor vehicle comprising a housing (12) having an inlet (14) and an outlet (16); a first brick (18) positioned inside the housing adjacent the inlet for initiating catalytic light-off functions of exhaust gases flowing through the first brick; a second brick (20) positioned adjacent the first brick downstream of the inlet for three way conversion of exhaust gases flowing through the second brick; a third brick (22) positioned adjacent the second brick downstream of the inlet for hydrocarbon adsorption and oxidation of exhaust gases flowing through the third brick; and a fourth brick (24) positioned adjacent and spaced from the third brick downstream of the inlet for light-off of exhaust gases flowing through the fourth brick; wherein the third brick is substantially annular with a through bore (28) extending axially therethrough; and wherein the second brick has a closed bore (30) extending axially and opening into the through bore of the third brick.