I want to preface this by saying that I have done an extensive search and could not find any info on this topic. I just had an alternator replaced today and after I picking it up from my mechanic, driving it home and parking it in my dirive way I noticed the idle was a little lower than normal. The was also a slight tap. So I revved the engine a little and when the rpms dropped it stalled out. I started it again revved it and had the same result.
It is a 99 a4 2.8 quattro 5spd.
Please help if you can.

 

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