I agree.  Basically, worn alt belt.  But what do I know?
Michael in San Antonio
91GL Weekender AT 2.1L 'Gringo'

On Thu, Mar 24, 2011 at 11:31 AM, David Beierl <dbeierl@attglobal.net>wrote:

> At 12:04 PM 3/24/2011, Greg Potts wrote:
>
>> Hi Volks,
>>
>> There are two issues I have noticed recently with my 87 Wolfsburg...
>>
>> firstly, the alternator belt has been shrieking like a banshee; mostly
>> at start-up, but occasionally I have noticed it at stoplights or when
>> revving slightly as I am pulling away from the curb. The belt tension is
>> good and the belt seems to be in good shape.
>>
>
> How many millimeters (or tenths of an inch) can you depress it with
> your thumb?  If you can press it more than six tenths of an inch
> (used belt more than 1 meter long), it's too loose.  And the max
> deflection jumps from 5 mm to 15 mm (used belt) at one meter length,
> and our belts are only a bit over a meter long...
>
>
>  Over the weekend I swapped
>> the alternator with a good condition slightly used unit this week I am
>> seeing the same results.
>>
>
> Which is what leads me to the above question.
>
>
> The other thing I have noticed is that the alternator is not charging
>> until I throttle the engine up to around 2500 rpms. It sits at 12V after
>> I start the engine and doesn't rise to 14V until I blip the throttle.
>> Once it comes up to 14 it stays there until the engine is shut off
>> again, with minor drops depending on load.
>>
>
> Having to blip the throttle to get the alternator going is documented
> normal behavior, you should find it in your owners manual.  My '84
> always did it; my '89 doesn't.  2500 rpm sounds awfully high to get
> it started though.  I'd expect more like 1700-1800.
>
> Yrs,
> d
>