5K ALTERNATOR PROBLEM

[ang@indiana.edu]

Dear Audi enthusiasts,

I have a 87 Audi 5Kcst and just changed the alternator few weeks ago 
because my machanic said my alternator had only about 28-30amp output and 
he said that is also the cause of my car cannot to start. After I changed 
the alternator I thought every thing will be fine. Until last week in a 
rainly day my brother drove the car to school as usual and suddenly the 
battery sign lighted up with a beep when the headlight, a/c and 
screenwiper was on. After that I check the voltage when the engine is 
idle and found is only 12.2V - 11.8V with a/c turn on and 10.9V - 11.4V 
with a/c and headlight turn on, the voltage even low when I turn all
the things on. The voltage will be a little bit high, about 11.8V - 12.0V,
when the car is running. The battery is about 6 months old and is fine. 

The problem is when I took my car to three different machanics to the check 
the electrical system they all said my alternator and battery is fine. 
But every times I get my car back the low voltage problem still exist.
This morning I went to start it, it would barely turnover. I just don't 
know what going on. I love my car and I really want my car back to normal, 
could anyone be kind to give me some advice about this problem ?

-Albert Ng-
ang@indiana.edu