Friday was driving home, been driving for perhaps 30mins, and stopped at lights. Car idled at about 1500 RPM, then gradually settled to ~1000 So i fired up my ODB app and it shows an error P0507 Idle Air Control System RPM higher than expected. Today, idle again was high - maybe 900. Resulting in engine light coming on. A few short trips later, light is off. Idle normal for now. My phone has saved the error if I need to speak to a dealer Weird eh.