[cutthroat1117]

As the guy above has said: It could be anything. But, the most common things are your Mass Airflow Sensor, and your Gas Cap. for your MAS, just take a peek at the filter, or maybe wipe off the probe with a clean cloth (the probe is mounted to the top of the lil...circular chamber thing. There's a wire coming from it)... Easiest test for the filter is holding it up to light: If it comes through, its clean, if the light's obstructed, it's dirty. At this point, you can blow the filter out with compressed air, buy a new filter ($20 - $60 depending what you're getting), or you can take the cheap/temporary way out and just turn the filter 90 degrees so the air flows through the unobstructed portion of the filter.

hope that helps