I have a 2001 Nissan Altima that is not a fan of the cold weather. In the morning when I start it up and put it in gear (automatic trans.) it idles fine. As soon as I give it some gas to pull out of the driveway, the car starts bucking and sputtering mostly leading to a stall. When I start it up again and place it in either drive or reverse from neutral, it instanly stalls again, unless of course I have the tach redlined and don't care about my tires! I need help in diagnosing this problem. I've heard maybe throttle position sensor? I just changed the plugs, so I know its getting good spark. Help!! :?