Alternator Identification
 

My alternator went on my 2001 A4 Avant Quattro, it is a V6 ATQ engine. Is there an easy way to identify if it is 90 or 120 Amp? I pulled it but there are no labels on it, one or two stamps on the voltage regulator say Bosch but no part numbers whatsoever. Looking at the options ECS Tuning sells it looks like a Bosch and not a Valeo.

Also is there a way to tell if it is the alternator versus the voltage regulator?

But there is more, pulling the alternator I noticed a broken wire, it goes to a plug that goes in upside down (wires exit downwards) about six inches above and slightly behind the fan switch in the lower radiator hose and a few inches outside of the alternator. Not sure what it goes into, it a cylinder, smaller than a soda can.

Turns out to be the auxiliary water pump, not on any audi diagrams (at least not on the 2.8, I did see it on a 2.7T), the hoses might show up on a Passat parts list if you get lucky. My hoses were shot, local auto parts store was able to find them on their diagram:

078-121-096-L Auxiliary water pump outlet (Top) to Thermostat housing
078-121-096-Q Auxiliary water pump inlet (Bottom) to Water Pipe

Nice of Audi to add the pump late in the B5 and not document it well.