Your sure not giving me much to go on here... If your also experiencing hard starting, it's often the temp, sensor is bad... A clogged air or gas filter will give you similar results, so will a faulty EGR valve... First replace the Temp sensor. It's under the top radiator hose. This often works wonders, it is a cheap part ($15) and the most likely place to start. Second, I would replace the fuel filter. Unfortunately, the fuel pump is also a possible issue here, but go with the fuel filter first... If your problem continues after the temp sensor and fuel filter are changed, turn the car off, without cranking it, turn the ignition switch on all the way to wher your about to crank the engin and then back off, about three times, then try to start the car. If it starts up and runs normal, even for a little while, it's your fuel pump... Before messing with that, remove the throttle body and clean it up with a tooth brush and some gas, so there is no carbon build up and it's squeaky clean. Then, while you have it off the car, on the back of the throttle body, around where the throttle place spring is on the front of the throttle body, the lower plug is Idle control valve. It's usually held o with two torx head screws. Remove it slowly and carefully, making sure you do not lose the rubber "O" ring... Rub it with a little brake fluid and use it when you reinstall the ICV, first, of course, cleaning it and where it goes into, with a toothbrush and some gas, or carb cleaner... I'm from the old school, so we use gas and kerosine mixed(Cheap) When you bolt everything back together, pour about 6 ounces of acetone into a full tank of gas, do the math if your tank isn't full, an ounce one way or the other will not matter much... Then take the car on a Highway drive for about 30 minutes... That usually does it... Before changing the fuel pump, repalce the fuel pressure regulator... If your still having problem, decide how much time and/or $$$ it's worth sinking into a 15 year old car, that basically was a shit box when they made them... Good Luck... LP