Cadillac Seville STS ’96

Good morning This is my first post at once, but I have read through some posts now, since I am the proud owner of my first Cadillac. But now I have a question and I noticed with the running engine that such a grinding noise comes here and have looked once with open hood and found the timing belt(?). For the first time of course a bit astonished, because I thought the Northstar was operated with control chain. I will now be warscheinl I’m outing as an absolute newcomer, but this may be quiet as I am. The “dental belt” I’m talking about is this one here: http://www.caddyinfo.com/46_lg.jpg Funny as well, the teeth are missing, so it won’t be the timing belt, but the timing belt? It’s the following model: Cadillac Seville STS 96 Cadillac Northstar 4.6 V8 As also stated on this page: http://www.aa1car.com/library/2002/us100232.htm Before I continue with any words and uncertainties I’m waiting for your answers and I hope for help, because at least I want to know what my car is doing under the hood and not that I’m driving this car in the ground – completely meaningless. I think that the grinding of this thing comes very probably, at least when I go after my ear. My uncle, who understands about cars, meant it was something with one or more Lagers, which have to be re-educated (?). What do you think it might be? Is such a remote diagnosis even possible? With help I would be very imaginable and hope that I will get some tips from my side of laymanship.