a method for controlling fueling of an engine , the method comprising during an engine cold start and before the engine is warmed to a predetermined level , transitioning from open - loop fueling to closed - loop fueling , where during closed - loop fueling feedback from an exhaust gas oxygen sensor is utilized and where said closed - loop fueling generates a cycling of delivered fuel in maintaining exhaust air - fuel ratio at a desired level ; and providing a fueling adjustment to a subsequent engine start in response to fueling information , said fueling information obtained over at least a complete cycle of closed - loop fueling following said transition from open - loop fueling .