S3 engine whitsle noise and revs up and down Help

[PORTER22]

Not had my s3 long but noticed today that there is a whistling noise on idle and at low rpm also the rev jump up and down at idle anyone any ideas

Any help would be great

 

[s3_trev]

Erratic idle can point to PCV valve. You say you have not had it long....did it come with service history? How many miles on it?

 

[PORTER22]

Erratic idle can point to PCV valve. You say you have not had it long....did it come with service history? How many miles on it?

Yeah it's full audi history 2009 58 plate 41k miles it's making a inttermiting whistle noise on low rpm to heard that can be the same symptoms