5ktq electrical issues update...

[Huw Powell]

> I'm confused. Seems theres 2 problems, 1 with intermittent charging,
> and another with something not getting enough voltage when the
> battery is at or below 12.8 causing the miss. Seems when it charges
> right it charges enough to mask the missfire issue by keeping the
> voltage up above that 12.8v mark.

I agree.  You have really got to stop mixing the two up, as it makes you
(and others) go back and forth between them.

I would tackle the charging system first, since it is simpler.  You have
already pretty much checked all your connections and grounds - except
for that splice under the passenger side carpet.

It's time to 1. get your battery load tested; 2. get your alternator
tested (it may put out the right voltage but not enough current, may be
producing a nasty waveform, etc.).  You should at least remove the
voltage regulator/brush assembly on the back of the alt. and measure the
brushes.

If you have a charging problem, focus on it and fix it first, then worry
about the issues with problem two.

As far as problem 2, I think although it seems to coincide with a drop
in voltage, you are chasing a red herring.  Any automotive equipment
that won't work at, say, 11.5 volts has something drastically wrong with
it.  After all, your car starts, and under cranking conditions it is
quite likely a few things are seeing under 12v.  I have driven my coupe
until it dropped to below 10v, something finally stopped working around
9-9.5 volts (had lost the alt belt and tried to drive home).  Admittedly
it is a very different set of systems running, but the general idea
still holds.

--
Huw Powell

http://www.humanspeakers.com/audi

http://www.humanthoughts.org/