The groaning noise your hearing is likely the IAC (idle air control) sticking because its gummed up and when this happens it moans. The fix usually is to remove it and clean it. It mounts to the throttle body and is held on By 2 8mm bolts. Remove it and take some carb cleaner and clean it with Q-tips, reinstall it and you should be ok. Im sending a picture to assist with locating it. If cleaning dosnt repair it then it will need repalcement.