Voltage reg?

[Cody Forbes]

Update:
On the way home it got more interesting. With no loads it now charges  
at 13.8-14v steady at idle, and fluctuates 13.4-13.8v above idle. As  
we got closer to home I turned on a bunch of loads including lights.  
It dropped to 12.5v initially, but after a few seconds crept back to  
13.3v. It still is fluctuating more that I like, but overall the thing  
just seems to be better than it has in many years. It's beyond me why  
it charges more at idle than it does above idle. I'll keep it under  
supervision and post if anything changes.

I got a note or two about that it should always charge 13.5 or better.  
Yes, this is true for nearly every car out there, but it just doesn't  
work out like that on a 5000. Most 5000's charge at a very peak of  
13.5 under ideal conditions  with voltages under heavy load being  
less. The only real fix is Avi Merons Ultranator or at least the VR he  
uses.

-Cody (mobile)

On May 15, 2010, at 5:35 PM, Cody Forbes <cody at 5000tq.com> wrote:

> I haven't seen a failure mode quite like this before so I shal employ
> the collective wisdom. Seems like a voltage regulator failing, but
> could maybe be bigger.
>
> So I'm cruising down the road in my '87 5ktq taking the family to the
> mall. At one point I noticed the tach fluctuate a little. Not quite
> like the old bouncing tach syndrome, just a lazy ~300rpm occillation
> while the engine was definately steady. I pulled up the volt meter in
> the climate control head and noticed that we were down to 10.3v. I
> immediately turned off the A/C and the voltage came quickly up to
> about 12.5v. This car has never been a great charger for the 4 years
> I've known it and two that Ive owned it, usually 12.8-13.0 daytime and
> low 12's at night with lights and everything going. Anyways, when I
> stopped at the next light the voltage very quickly rose to 14.0v with
> the engine at idle. As soon as I raised the revs to pull away it
> dropped back to 12.5v. We were more than halfway to our destination so
> I decided to motor on. On the highway voltage fluctuated 12.3-12.9.
> Back off the highway I noticed the voltage fluctuating with the
> cooling fan as it should, but it was swinging from about 12.3 with the
> fan on to near 13.8 when it turned off.
>
> -Cody (mobile)
> _______________________________________________
> quattro mailing list
> http://www.audifans.com/mailman/listinfo/quattro
> http://www.audifans.com/kb/List_information