Joe, thanks for the reply. Are you suggesting the Mass Air Sensor (MAS) based on the check engine code, the symptoms, or both? The reason I ask is that the car drove fine when I got the "Fuel Trim" code, and now that it is driving bad, I get no check engine warnings.

I would also like to point out that it idles fine, no stalling. The times that it wouldn't start were after my wife was doing quick errands, so the engine was hot. The hesitation happened when the engine was cold.

Does this still sound like MAS?