Method for performing evaporative emission system diagnostics on engines configured for stop-start operation

摘要

A method of operating an engine in a vehicle equipped with an evaporative emissions system is described. The engine is configured to perform automatically an engine stop and an engine restart when the vehicle stops moving to increase fuel economy of the vehicle. The method includes the steps of determining if an engine stop is allowed while a diagnostic test of the of the evaporative emissions system is being performed if an engine stop is requested, and preventing the engine stop if the engine stop is not allowed.