Recently my S3 has been hesitating for split second around 1800RPM - 2000RPM while driving i can feel it and its starting to annoy me. On the journey to work today i noticed the engine while sitting still at traffic lights sometimes vibrates the car like a V8. Again for a second on idle. The needle does not sit still either on idle not weavering fast just very slight movement up and down. Car pulls fine above 2500RPM but seems a little reluctant lower down.... Any suggestions? MAF?