Hey guys, I am having the same issue ....HOWEVER,
my 96 R33 GTST (100km covered), was due for a timing belt, especially as I only just got the car a few months ago and didn't know if its been done.
I bought a timing kit, had it fitted, and within 2 weeks I am getting a whirr/growl from top of timing cover,
the noise only happens a few hundred RPM over idle and goes when revved higher, I have noticed that the growl goes once its warm (after a few mins) but have also notice when quite hot... I am getting a high pitched groan/moan from the same area.
Is the idler bearing shot? or tensioner? or is it just a noisy belt?
My other concern is that the tensioner has been set too tight and its worn the bearings ... is this possible?
Note, The noise wasn't there before the timing belt was done.
Muchly appreciated if anyone else can shed some light?
Andy