[Vwdiesel] Cont'd Electrical gremlins - bad ground?

[Lee Hillsgrove]

 The problem is that my car is often losing the charge
>at the battery. Went out this morning and the battery is putting out about
>11.85 volts, not quite enough to crank it with a long glow plug cycle (I'm
>in Southern Maine, it's cold enough all ready at 6:45 AM)
>I had my alternator rebuilt at a  local shop a few weeks ago, so I'm going
>to assume it's okay now. The alternator light has been lit up recently when
>the engine speed goes up before I shift, then it goes off.
<snip>
>The alternator is putting out the proper voltage when it's running (right
>around 13.9 volts). The battery is getting a proper charge when the car is
>running as well from my multimeter testing results. I had the battery
>tested and it is good according to the Autozone guy that tested it.
>

<snip>
 I'm suspecting it's just a really bad ground not
>allowing the battery to fully charge, but am not really sure. Any ideas?
>Thanks in advance.
>



  It almost sounds like a light may be getting left on or something else is
draining the battery. If you are getting 13.9 V while it's running, and the
battery is indeed good, it should maintain a charge overnight. On the other
hand, almost 12 volts when not running isn't that bad, so you may have some
other problem.
 After the battery is charged, I'd do this:
While cranking the engine over, measure voltage between the negative battery
post and the engine. You can pull the stop solenoid wire to prevent the
engine from starting  while you do this. If the negative side of the circuit
is good, you should see almost nothing for a voltage. Do the same between
the large terminal on the starter and the positive battery terminal to check
the other side of the circuit.
 You could also (with the engine off) disconnect one terminal of the battery
and measure voltage and/or current between the battery and cable to see if
there is a parasitic drain while the car is off. The trunk light has been
known to stay on in some cars. Sorry, I don't remember what you have for a
vehicle.
 The other real possibility is that your starter is not up to snuff. I'm
assuming that the symptom is slow cranking speed as well. The fix for that
is often a set of brushes.

 Pretty nippy here in central NH this morning, too! You should see how the
TDIs start in this weather - no fuss whatsoever. Mighty clattery until it
warms up, especially with the timing set to the top of the range.

 Good luck, and let us know what you find.


  Lee
  Oo-v-oO
  PP-ASEL
  KB1GNI