You may have a very dirty IAC (Idle Air Control) it's the cylindrical looking thing ,attached to your throttle body ,with the electrical lead coming off the bottom of it . You need to remove it (2 bolts ,and disconnect the lead ) do youself a favour and disconnect the battery ( for at least 30 mins ,while you are cleaning the IAC ) soke it some carb cleaner ,(after you have removed ,the solenoid part of it (by removing the 2 phillips head screws) soke it , assemble it ( be careful with the removal of the gasket ) most times you can reuse it over ,over again . then after you connect the lead , connect the battery . this should calm your idle woes
