Integrated Air Fuel Catalyst Monitor Method

The integrated air fuel catalyst monitor method is used as the on board strategy designed to monitor the oxygen storage capacity of the catalyst after a deceleration fuel shut off (DFSO) event. The monitor determines the amount of fuel needed to drive the catalyst to a rich condition when starting from an oxygen saturated, lean condition. The monitor is a measure of how much fuel is required to force the catalyst from a lean to a rich condition. The monitor runs during fuel reactivation following a DFSO event. The monitor completes after a calibrated number of DFSO monitoring events have occurred.