Razors4us

I seem to have a howling/growling/humming that comes and goes intermittently from the front of the engine near the alternator. I grabbed my stethoscope probe and the sound is much more prevalent when I touch the probe to the front mount. It's dead silent everywhere else. It's been a very long time since I've owned one of these cars and I just picked up this gorgeous s8 for super cheap so I'd like to get it squared away. That being said, is it possibly oil pump related? That seems to be the only thing I can think of up in that area that would make noise aside from the alternator which doesn't make a peep. The timing belt and tensioner and idlers are all brand new including water pump.

jfrahm

Can you unplug the electrical lead to the engine mount? It's 4D0199381AT if you want to google up a pic.

Razors4us

Seems to be exclusively down near the alternator. It's a constant whirring/humming noise. With the stethoscope probe it seems most prevalent when I put it directly on the front snub mount

jfrahm

I guess try pulling the serpentine belt? The tensioner bearings go bad, alternator bearings, fan support bearing, etc.
The tensioner roller can be replaced with a roller for a Hyundai 2.7L engine, Audi seems to only sell the whole tensioner unit for a lot more money.
The idler lasts a lot longer but it's cheap and easy to replace, it's on the opposite side from your noise but if you are replacing stuff it's not a bad idea to change it.