Daimlerchrysler Corporation

Bill Leisenring

Wei D Wang

Richard K Moote

Chris J Booms

Mark J Poublon

Douglas M Stander

Jason E Wielenga

Danny K Schuelke

Craig Summers

Tom Stephens

Dave Carlson

In a motor vehicle having an engine with an exhaust catalyst and an oxygen sensor upstream of the catalyst and an oxygen sensor downstream of the catalyst, a method for detecting whether the catalyst has aged. Over a test block period of time, the method periodically obtains upstream data points from an oxygen sensor located upstream of the catalyst and from and oxygen sensor located downstream of the catalyst. Absolute differences are calculated between consecutive pairs of the upstream data points and the downstream data points. A ratio between the sums of absolute differences is then calculated, and the ratio is used to determine whether the catalyst has aged.

Exhaust catalyst monitoring arrangement

Growing community of inventors

Tecumseh, MI, United States of America

Bill Leisenring