First Welcome.... Did you have any issues registering? I changed it to require a word recognition and checking to make sure it wasn't a problem.
Second... Year, mileage, last tune up, grade of fuel you use, if a D1 last fuel filter change.
If I were to guess I would say Dirty MAF (Mass Air Flow sensor) or TPS (throttle Position Sensor, or IAC (Idle Air Control).
The more info you provide the better chance we can help.