147 2.0l selespeed rev noise rattle

[dave 147]

Just nitced to day just over tick over with a sligth bit of trotel on sort or a woring/squeaking noise very hard to describe it cant be gud but goes away with a couple 100 more rpm and doesnt come back till it drops back in revs and it only hapens in a 100 rpm range any ideas, the car runs fine no drop of in performance or any thing like that i first thought the exzorst was blowing but not so sure now

all help welcome bit worried

Dave