From what it sounds like your having a problem with your Mass Air Meter. This is a sensor that detects how much air is going into your engine and with the help of the computer it's hooked to will tell how much gas is to be introduced so the car will go. You may or may not need a new one but you should have it checked into so that it will not leave you stranded. These parts are expensive, and I have had good results buying used ones from Ebay.
Hope that helps
Poolman