5ktq electrical problems update (not fixed)

[Cody Forbes]

>
> >>So where are you measuring the voltage at?
> >
> > Measuring voltage usually at the battery, ECU, rad fan, and front engine
bay
> > battery access terminal. Also a few other places sometimes.
>
> Good.  The other half of that question is, where are you grounding your
> meter for each of these measurements?

Various spots. Battery obviously to the neg terminal, anything in the engine
compartment I usually go to the intake manifold or cylinder head. Inside the
car either bat neg again or I like the screws in the door jam that hold the
upper doorjam trim on the windsield frame They seem to be clean and good
grounds since they look like they are somewhat new and never painted over.

>
> > I assume the alternator grounds through the engine because there is no
> > ground wire on it. Its solidly bolted on.
>
> That is correct.  Have you checked that solid bolting for corrosion or
dirt?

Not thuroughly(sp?) but quick visual without taking them out they look the
usual dirty but not rusty or coroded. I may take the nuts off and make sure
they are clean underneath today if it comes to that.

>
> Have you taken a close look at the small wire (should be blue) going to
> the alternator yet?  Measured its voltage at idle and with lights on?
>

Nope, havent done that. Will do today. A song comes to mind......"Makin a
list...Checkin it twice....lookin to see if the grounds are naughty or
nice...." lol.

> Have you checked the voltage at idle/under load (lights on) at places
> like the power feed to the ignition computer?

Ignition computer and EFI copmuter share the same power feed, and I always
am monitoring the voltage through the EFI with the laptop because it stays
very very close to bat voltage and is convientient for quick glances.

>
> There's something really odd wrong if your systems are failing when the
> car is still above 12 volts, something besides a possible charging issue.

I agree the main problem most likely isn't the charging system (though it
could be a contributor),  but since I'm working in the same areas I'm
checking out the charging system (and every electrical _anything_) as I
work.

>
> --
> Huw Powell
>
> http://www.humanspeakers.com/audi
>
> http://www.humanthoughts.org/
>
>
>

-Cody Forbes
Black Forest Racing
2x '86 5ktq
'87 5ktq
'88 80 4cyl