ENGINE MANAGEMENT STRATEGY TO IMPROVE THE ABILITY OF A CATALYST TO WITHSTAND SEVERE OPERATING ENVIRONMENTS

摘要

A method and engine control strategy is described that enables improved catalyst performance after having been exposed to severe operating environments. More specifically, rhodium-containing catalysts are reactivated by being subjected to fuel-rich spikes after being exposed to high temperature, excess oxygen conditions which typically arise during programmed fuel-cut engine control strategies. Thus the present invention represents a departure from current control strategies by providing fuel-rich spikes during engine control modes when conventional practice is not to provide rich-fuel spikes.